UPSC Environment & Ecology PYQs (2014-25) with Solved Answers

ENVIRONMENT AND ECOLOGY

Q1. According to the Environmental Protection Agency (EPA), which one of the following is the largest source of sulphur dioxide emissions? [UPSC CSE Pre 2024]

(a) Locomotives using fossil fuels
 (b) Ships using fossil fuels
 (c) Extraction of metals from ores
 (d) Power plants using fossil fuels

Explanation:
 EPA’s national ambient air quality standards for SO₂ are designed to protect against exposure to the entire group of sulfur oxides (SOₓ). According to EPA, the largest source of SO₂ in the atmosphere is the burning of fossil fuels by power plants and other industrial facilities. Smaller sources of SO₂ emissions include industrial processes such as extracting metal from ore, natural sources such as volcanoes, and locomotives, ships, and other vehicles and heavy equipment that burn fuel with a high sulfur content.
 Hence, option (d) is the correct answer.

About EPA:
 The Environmental Protection Agency is an independent agency of the United States government tasked with environmental protection matters.

Q2. Consider the following statements: [UPSC CSE Pre 2024]

Statement-I: India does not import apples from the United States of America.
 Statement-II: In India, the law prohibits the import of Genetically Modified food without the approval of the competent authority.

Which one of the following is correct in respect of the above statements?

(a) Both Statement-I and Statement-II are correct, and Statement-II explains Statement-I
 (b) Both Statement-I and Statement-II are correct, but Statement-II does not explain Statement-I
 (c) Statement-I is correct, but Statement-II is incorrect
 (d) Statement-I is incorrect, but Statement-II is correct

Explanation:
 In February 2024, US lawmakers and apple growers celebrated the export of apples to India, which was 16 times more than the previous year. This increase followed India’s decision to drop the 20% retaliatory tariff imposed in 2019 on American products. Earlier in 2019, in retaliation for the then-Trump Administration’s decision to revoke India’s trade benefits under the Generalised System of Preferences (GSP) programme, India imposed several retaliatory tariffs on American products, including apples. Hence, Statement-I is incorrect.

As per the import policy of Genetically Modified (GM) Food, Feed, Genetically Modified Organisms (GMOs), and Living Modified Organisms (LMOs), the import of GM food requires prior approval from the Genetic Engineering Approval Committee (GEAC), which is constituted under the Ministry of Environment, Forest and Climate Change. Additionally, the import of food products is regulated under the Food Safety and Standards Act (FSSAI), 2006. Indian Customs can clear food products, including Genetically Modified (GM) food products, only after receiving necessary approval or a No Objection Certificate (NOC) from FSSAI. Hence, Statement-II is correct.

Thus, the correct answer is option (d): Statement-I is incorrect, but Statement-II is correct.

Q3. Consider the following statements: [UPSC CSE Pre 2024]

Statement-I: Many chewing gums found in the market are considered a source of environmental pollution.
 Statement-II: Many chewing gums contain plastic as gum base.

Which one of the following is correct in respect of the above statements?

(a) Both Statement-I and Statement-II are correct, and Statement-II explains Statement-I
 (b) Both Statement-I and Statement-II are correct, but Statement-II does not explain Statement-I
 (c) Statement-I is correct, but Statement-II is incorrect
 (d) Statement-I is incorrect, but Statement-II is correct

Explanation:
 Modern chewing gum consists of four groups of ingredients that contribute to its texture, flavor, and elasticity:

1. Fillers such as talc and calcium carbonate add bulk.
2. Polymers (like polyvinyl acetate) provide stretch and form the "gum base."
3. Emulsifiers help mix flavors and reduce stickiness.
4. Softeners (such as vegetable oil) maintain chewiness.

Statement-I is correct because chewing gum is a significant source of environmental pollution. It is non-biodegradable and contributes to plastic waste that lingers in the environment for years.

Statement-II is also correct as many chewing gums contain polyvinyl acetate (PVA), a plastic-based substance used in manufacturing tires and glue. According to research, chewing gum generates over 105 tonnes of plastic waste annually, making it a severe environmental hazard.

Since the plastic content in chewing gum directly contributes to its role in pollution, Statement-II correctly explains Statement-I.

Thus, the correct answer is (a) Both Statement-I and Statement-II are correct, and Statement-II explains Statement-I.

Q4. Which one of the following shows a unique relationship with an insect that has coevolved with it and that is the only insect that can pollinate this tree? [UPSC CSE Pre 2024]

(a) Fig
 (b) Mahua
 (c) Sandalwood
 (d) Silk cotton

Explanation:

• Many species of fig trees (Ficus) have an exclusive, coevolved relationship with a specific species of wasp, known as the fig wasp (Agaonidae family).
• Each fig species is typically pollinated only by its corresponding wasp species, making this a classic example of obligate mutualism.
• The fig wasp enters the fig's enclosed inflorescence (syconium) to lay eggs and, in the process, pollinates the flowers inside.
• In return, the developing wasp larvae consume some of the fig seeds, benefiting both species.

Since fig trees rely solely on fig wasps for pollination, the correct answer is:

(a) Fig.

Q5. Consider the following: (UPSC - 2024)

1. Butterflies
2. Fish
3. Frogs

How many of the above have poisonous species among them?

(a) Only one
 (b) Only two
 (c) All three
 (d) None

Explanation:

• Butterflies: Some butterflies are poisonous due to the toxins they accumulate from their host plants. The African giant swallowtail (Papilio antimachus) is the most poisonous butterfly in the world, containing cardiac steroid toxins potent enough to harm predators.
  
  
• Fish: Several species of fish are venomous, with the Reef Stonefish (Synanceia) being the most venomous fish in the world. It has thirteen dorsal spines that inject venom, causing extreme pain and even fatalities.
  
  
• Frogs: Many frog species are poisonous, such as poison dart frogs (Dendrobatidae family), which secrete potent toxins through their skin. Additionally, there are two species of venomous frogs—Bruno's casque-headed frog (Aparasphenodon brunoi) and Greening's frog (Corythomantis greeningi)—which not only secrete poison but also use spiny bone projections to inject venom.
  Since all three groups contain poisonous species, the correct answer is:

(c) All three.

Q6. Consider the following: (UPSC - 2024)

1. Cashew
2. Papaya
3. Red sanders

How many of the above trees are actually native to India?

(a) Only one
 (b) Only two
 (c) All three
 (d) None

Explanation:

• Cashew (Anacardium occidentale) is not native to India. It originates from northeastern Brazil and was introduced to India by Portuguese traders in the 16th century.
• Papaya (Carica papaya) is not native to India. It is believed to have originated in southern Mexico and Central America before being introduced to other tropical regions, including India.
• Red sanders (Pterocarpus santalinus) is native to India, particularly to the southern Eastern Ghats of Andhra Pradesh. It is highly valued for its deep red wood and is listed under CITES Appendix II due to concerns over illegal trade.

Since only Red Sanders is native to India, the correct answer is:

(a) Only one.

Q7. Consider the following:

1. Carabid beetles
2. Centipedes
3. Flies
4. Termites
5. Wasps

Parasitoid species are found in how many of the above organisms?

(a) Only two
 (b) Only three
 (c) Only four
 (d) All five

(UPSC Pre 2024)

Explanation:

Parasitoids are organisms that live in close association with a host, eventually killing it. They are primarily found among insects.

• Carabid beetles (1) have parasitoid species in some genera like Brachinus, Lebia, and
• Flies (3) (Diptera) contain many parasitoid species, particularly in families like
• Wasps (5) (Hymenoptera) include the largest group of parasitoids, such as Braconidae and

However,

• Centipedes (2) are predators, not parasitoids.
• Termites (4) are detritivores, not parasitoids.

Thus, parasitoids are found in three of the given organisms.

Answer: (b) Only three.

Q8. Consider the following plants:

1. Groundnut
2. Horse-gram
3. Soybean

How many of the above belong to the pea family?

(a) Only one
 (b) Only two
 (c) All three
 (d) None

(UPSC Pre 2024)

Explanation:

The Fabaceae (Leguminosae) family, commonly known as the pea family, includes many important legumes.

• Groundnut (1) belongs to Fabaceae.
• Horse-gram (2) belongs to Fabaceae.
• Soybean (3) belongs to Fabaceae.

Since all three belong to the pea family, the correct answer is:

Answer: (c) All three.

Q9. Consider the following statements:

Statement I: The Indian Flying Fox is placed under the “vermin” category in the Wildlife (Protection) Act, 1972.

Statement II: The Indian Flying Fox feeds on the blood of other animals.

Which one of the following is correct in respect of the above statements?

(a) Both Statement-I and Statement-II are correct, and Statement-II explains Statement-I.
 (b) Both Statement-I and Statement-II are correct, but Statement-II does not explain Statement-I.
 (c) Statement-I is correct, but Statement-II is incorrect.
 (d) Statement-I is incorrect, but Statement-II is correct.

(UPSC Pre 2024)

Explanation:

• Statement I is correct: The Indian Flying Fox (Pteropus giganteus), a fruit bat, was listed under Schedule V (vermin category) of the Wildlife (Protection) Act, 1972, but was later moved to Schedule II, providing it higher protection.
• Statement II is incorrect: The Indian Flying Fox is frugivorous (fruit-eating), not a blood-feeding animal like vampire bats.

Since Statement I is correct, but Statement II is incorrect, the correct answer is:

Answer: (c) Statement-I is correct, but Statement-II is incorrect.

Q10. Consider the following materials:

1. Agricultural residues
2. Corn grain
3. Wastewater treatment sludge
4. Wood mill waste

Which of the above can be used as feedstock for producing Sustainable Aviation Fuel (SAF)?

(a) 1 and 2 only
 (b) 3 and 4 only
 (c) 1, 2, 3, and 4
 (d) 1, 3, and 4 only

(UPSC Pre 2024)

Explanation:

Sustainable Aviation Fuel (SAF) is a low-carbon biofuel that can be produced from various sustainable feedstocks, including:

• Agricultural residues (1) – Used for biofuel production.
• Corn grain (2) – Can be processed into bioethanol-based SAF.
• Wastewater treatment sludge (3) – Contains organic matter useful for biofuel production.
• Wood mill waste (4) – Provides lignocellulosic biomass for SAF.

Since all four options are viable feedstocks for SAF, the correct answer is:

Answer: (c) 1, 2, 3, and 4.

Q11. Consider the following pairs of Wetlands/Lakes and their Locations (UPSC CSE Pre 2022):

1. Hokera Wetland – Punjab
2. Renuka Wetland – Himachal Pradesh
3. Rudrasagar Lake – Tripura
4. Sasthamkotta Lake – Tamil Nadu

How many of the above pairs are correctly matched?
 (a) Only one
 (b) Only two
 (c) Only three
 (d) All four

Solution: (b)
 Explanation:

• Pair 1 is incorrect. Hokera Wetland is in Jammu and Kashmir, not Punjab. It is a natural perennial wetland contiguous to the Jhelum basin.
• Pair 2 is correct. Renuka Wetland is the largest natural lake in Himachal Pradesh. It is a freshwater wetland fed by a small stream flowing to the Giri River.
• Pair 3 is correct. Rudrasagar Lake, also known as Rudijala, is located in Tripura and is designated as a Ramsar site.
• Pair 4 is incorrect. Sasthamkotta Lake is in Kerala, not Tamil Nadu. It is the largest freshwater lake in Kerala and an important tourist attraction.

Q12. The statement "If rainforests and tropical forests are the lungs of the Earth, then wetlands function as its kidneys" highlights which of the following functions of wetlands? (UPSC CSE Pre 2022)

(a) The water cycle in wetlands involves surface runoff, subsoil percolation, and evaporation.
 (b) Algae form the nutrient base upon which fish, crustaceans, mollusks, birds, reptiles, and mammals thrive.
 (c) Wetlands play a vital role in maintaining sedimentation balance and soil stabilization.
 (d) Aquatic plants absorb heavy metals and excess nutrients.

Solution: (d)
 Explanation:
 Just as forests are the "lungs of the Earth," wetlands act as "kidneys" by filtering and purifying water. Aquatic plants in wetlands absorb heavy metals and excess nutrients, preventing water contamination. For example, mangroves store metals and immobilize pollutants, playing a crucial role in maintaining water quality.

Q13. With reference to polyethylene terephthalate (PET), consider the following statements (UPSC CSE Pre 2022):

1. PET fibers can be blended with wool and cotton to enhance their properties.
2. Containers made of PET can be used to store any alcoholic beverage.
3. PET bottles can be recycled into other products.
4. Articles made of PET can be incinerated without causing greenhouse gas emissions.

Which of the above statements are correct?
 (a) 1 and 3
 (b) 2 and 4
 (c) 1 and 4
 (d) 2 and 3

Solution: (a)
 Explanation:

• Statement 1 is correct. PET fibers are resistant to deformation and wrinkling, making them ideal for blending with cotton and wool to improve fabric durability.
• Statement 2 is incorrect. In states like Maharashtra, using PET containers for alcoholic beverages is banned due to health concerns. PET is commonly used for carbonated drinks but not for high-temperature liquids.
• Statement 3 is correct. PET is the most widely recycled plastic and can be repurposed into fiberfill, carpets, and other products.
• Statement 4 is incorrect. PET incineration releases harmful gases, including hydrocarbons and bisphenol-A, contributing to pollution.

Q14. In which of the following biogeochemical cycles is the weathering of rocks the primary source of nutrient release? (UPSC CSE Pre 2021)

(a) Carbon cycle
 (b) Nitrogen cycle
 (c) Phosphorus cycle
 (d) Sulfur cycle

Solution: (c)
 Explanation:

• The carbon and nitrogen cycles primarily involve gaseous exchanges with the atmosphere.
• The sulfur cycle has both sedimentary and gaseous components.
• The phosphorus cycle is mainly sedimentary, with rock weathering being the major process that releases phosphorus into ecosystems. This phosphorus is then utilized by plants and animals.

Q15. Which of the following organisms are detritivores? (UPSC CSE Pre 2021)

1. Earthworms
2. Jellyfish
3. Millipedes
4. Seahorses
5. Woodlice

Select the correct answer using the codes given below:
 (a) 1, 2, and 4 only
 (b) 2, 3, 4, and 5 only
 (c) 1, 3, and 5 only
 (d) 1, 2, 3, 4, and 5

Solution: (c)
 Explanation:
 Detritivores are organisms that obtain nutrition by feeding on decomposing plant and animal matter.

• Earthworms, millipedes, and woodlice are classic detritivores.
• Jellyfish and seahorses are carnivorous, not detritivores.

Q16. Which of the following groups contain species that can form symbiotic relationships with other organisms? (UPSC CSE Pre 2021)

1. Cnidarians
2. Fungi
3. Protozoa

Select the correct answer using the codes given below:
 (a) 1 and 2 only
 (b) 2 and 3 only
 (c) 1 and 3 only
 (d) 1, 2, and 3

Solution: (d)
 Explanation:

• Cnidarians (e.g., corals) form symbiotic relationships with zooxanthellae algae, providing them shelter while receiving nutrients through photosynthesis.
• Fungi engage in symbiosis with plant roots (mycorrhizae) and with algae to form
• Protozoa also form symbiotic associations, such as mutualism with bacteria or relationships with termites to aid digestion.

Q17. Consider the following statements regarding Coral Reefs: [UPSC CSE Prelims 2018]

1. Most of the world's coral reefs are located in tropical waters.
2. More than one-third of the world’s coral reefs are found within the territories of Australia, Indonesia, and the Philippines.
3. Coral reefs support a greater number of animal phyla than tropical rainforests.

Which of the statements given above is/are correct?
 (a) 1 and 2 only
 (b) 3 only
 (c) 1 and 3 only
 (d) 1, 2, and 3

Answer: (d)

Explanation:

• Statement 1 is correct: Most coral reefs are situated in tropical waters, specifically between the Tropic of Cancer and the Tropic of Capricorn, as they require specific environmental conditions such as warm temperatures and sufficient sunlight to thrive.
• Statement 2 is correct: Australia, Indonesia, and the Philippines collectively account for approximately 44% of the world’s coral reefs. Specifically, Indonesia hosts 95%, Australia 17.22%, and the Philippines 8.81% of the global coral reef area.
• Statement 3 is correct: Coral reefs exhibit a significantly higher biodiversity compared to tropical rainforests. While coral reefs support 32 out of the 34 known animal phyla, tropical rainforests contain only about 9 phyla as free-living species. This is due to the high biological productivity of coral reef ecosystems.

Key Facts about Coral Reefs:

• Coral reefs are massive underwater structures formed by reef-building corals (hermatypic corals) that extract calcium carbonate from seawater to build their hard exoskeletons.
• These ecosystems thrive in warm saline waters, preferring temperatures between 23°C and 29°C.
• Most reef-building corals are restricted to shallow waters, usually less than 30 meters deep, within 30°N to 30°S of the equator.
• Due to their immense biodiversity, coral reefs are often referred to as the "rainforests of the sea."

Q18. Which of the following leaf modifications help in reducing water loss in desert plants?

[UPSC CSE Prelims 2018]

1. Hard and waxy leaves
2. Tiny leaves
3. Thorns instead of leaves

Select the correct answer using the codes given below:
 (a) 2 and 3 only
 (b) 2 only
 (c) 3 only
 (d) 1, 2, and 3

Answer: (d)

Explanation:

Desert plants have evolved specific adaptations to survive in arid conditions:

• Statement 1 is correct: Many desert plants have hard and waxy leaves to reduce water loss. The waxy layer (cuticle) is made of cutin, a water-resistant compound that helps retain moisture.
• Statement 2 is correct: Desert plants often have tiny leaves to minimize the surface area exposed to sunlight, thereby reducing transpiration (water loss). Smaller leaves also prevent excessive heating.
• Statement 3 is correct: Some desert plants replace leaves with thorns to conserve water. Thorns also help deter herbivores from feeding on the plant.

Additionally, certain desert plants shed leaves during dry periods and regrow them when water availability improves. Others regulate their photosynthesis to optimize water use efficiency.

Q19. What does the term "carbon fertilization" refer to?

[UPSC CSE Prelims 2018]
 (a) Increased plant growth due to higher levels of carbon dioxide in the atmosphere.
 (b) Rising global temperatures caused by increased carbon dioxide levels.
 (c) Higher ocean acidity resulting from increased carbon dioxide concentration.
 (d) Adaptation of living organisms to climate change due to rising carbon dioxide levels.

Answer: (a)

Explanation:

• Carbon fertilization is the phenomenon where plants experience enhanced growth due to higher atmospheric carbon dioxide (CO₂) levels, which boost photosynthesis rates.
• The extent of this effect depends on several factors, including plant species, temperature, and the availability of water and nutrients.
• Additionally, greenhouses artificially enrich CO₂ levels to improve plant productivity.
• Elevated CO₂ levels can increase water-use efficiency in plants, making them more resilient to drought conditions.

Q20. What is Biological Oxygen Demand (BOD) used for?

[UPSC CSE Prelims 2017]
 (a) Measuring oxygen levels in human blood.
 (b) Calculating oxygen levels in forest ecosystems.
 (c) Assessing pollution levels in aquatic ecosystems.
 (d) Determining oxygen availability in high-altitude regions.

Answer: (c)

Explanation:

• Biological Oxygen Demand (BOD) is a key indicator used to assess the level of organic pollution in water bodies. It measures the amount of dissolved oxygen required by microorganisms to break down organic material present in a given water sample.
• A higher BOD value indicates a greater level of pollution, as more oxygen is consumed by bacteria decomposing organic waste.

Key Differences Between BOD and COD:

BOD (Biological Oxygen Demand)	COD (Chemical Oxygen Demand)
Measures the amount of oxygen consumed by microorganisms breaking down organic matter.	Measures the total oxygen required to chemically oxidize both organic and inorganic substances.
Indicates biological pollution levels.	Provides a broader assessment, including chemical pollutants.

Q21. If there is a significant decline in the population of butterflies, what could be the possible consequences?

[UPSC CSE Prelims 2017]

1. Pollination of certain plant species could be negatively affected.
2. A drastic rise in fungal infections affecting some cultivated crops.
3. A decline in the population of certain species of wasps, spiders, and birds.

Select the correct answer using the codes given below:
 (a) 1 only
 (b) 2 and 3 only
 (c) 1 and 3 only
 (d) 1, 2, and 3

Answer: (c)

Explanation:

• Statement 1 is correct: Butterflies play a vital role in pollination, particularly for flowering plants. A sharp decline in butterfly populations would reduce pollination efficiency, impacting plant reproduction.
• Statement 2 is incorrect: There is no direct correlation between butterfly population decline and an increase in fungal infections on cultivated crops.
• Statement 3 is correct: Certain species of wasps, spiders, and birds rely on butterflies as part of their food chain. A decrease in butterflies could disrupt predator-prey relationships, leading to population declines in these species.

Q22. What is the best description of the term 'ecosystem'?

[UPSC CSE Prelims 2016]

(a) A community of organisms interacting with one another
 (b) That part of the Earth which is inhabited by living organisms
 (c) A community of organisms together with the environment in which they live
 (d) The flora and fauna of a geographical area

Answer: (c)

Explanation:

• An ecosystem consists of a community of living organisms (biotic components) interacting with non-living elements (abiotic components) such as air, water, and soil within a specific environment.
• These interactions occur through nutrient cycles and energy flows, ensuring the functioning of the system.
• Unlike option (a), which only refers to organisms interacting with each other, an ecosystem includes both living and non-living factors that influence one another.

Key Features of an Ecosystem:

• Biotic components: Plants, animals, microorganisms.
• Abiotic components: Water, soil, sunlight, temperature.
• Energy flow: Sunlight → Plants (producers) → Herbivores (primary consumers) → Carnivores (secondary/tertiary consumers).
• Nutrient cycling: The continuous movement of elements like carbon, nitrogen, and phosphorus between organisms and the environment.

Thus, the correct definition of an ecosystem is "a community of organisms together with the environment in which they live" (option c).

Q23. Which of the following organisms are considered decomposers in an ecosystem?

[UPSC CSE Prelims 2014]

1. Virus
2. Fungi
3. Bacteria

Select the correct answer using the codes given below:

(a) 1 only
 (b) 2 and 3 only
 (c) 1 and 3 only
 (d) 1, 2, and 3

Answer: (b)

Explanation:

• Decomposers are organisms that break down dead organic material and recycle nutrients into the ecosystem.
• Fungi and bacteria are the primary decomposers as they decompose dead plants, animals, and organic waste.
• Viruses, however, do not decompose organic material; they invade host organisms and replicate, but they do not contribute to decomposition.

Thus, fungi and bacteria are the correct answers.

Q24. Why don’t trees replace grasses in grasslands during ecological succession?

[UPSC CSE Prelims 2014]

(a) Insects and fungi
 (b) Limited sunlight and lack of nutrients
 (c) Water scarcity and frequent fires
 (d) None of the above

Answer: (c)

Explanation:

• Grasslands exist in regions with moderate rainfall (25–75 cm per year), which is insufficient to support forests but more than what deserts receive.
• Water scarcity prevents the growth of large trees, and frequent wildfires further limit tree establishment.
• These factors ensure that grasses remain dominant and prevent the transition to a forest ecosystem.

Thus, water scarcity and fire are the main reasons why trees do not replace grasses in grasslands.

Q25. Where is the largest proportion of Earth's freshwater found, excluding ice caps and glaciers?

[UPSC CSE Prelims 2014]

(a) In the atmosphere as moisture and clouds
 (b) In freshwater lakes and rivers
 (c) As groundwater
 (d) As soil moisture

Answer: (c)

Explanation:

• Freshwater distribution on Earth is highly uneven.
• Only 3% of Earth's water is freshwater, with around 69% locked in glaciers and ice caps.
• Of the remaining freshwater, about 30% exists as groundwater, making it the largest available source.
• Less than 1% of freshwater is found in lakes, rivers, and swamps, and an even smaller amount is in the atmosphere.

Thus, the correct answer is groundwater as the largest freshwater reserve after ice caps and glaciers.

Q26. Which statements about food chains in ecosystems are correct?

[UPSC CSE Prelims 2014]

1. A food chain illustrates the order in which organisms feed on one another.
2. Food chains exist within the populations of a single species.
3. A food chain shows the number of organisms consumed by others.

Select the correct answer:

(a) 1 only
 (b) 1 and 2 only
 (c) 1, 2, and 3
 (d) None

Answer: (a)

Explanation:

• Statement 1 is correct: A food chain represents the sequence of organisms in an ecosystem where energy flows through consumption.
• Statement 2 is incorrect: Food chains do not exist within a single species; they represent interactions between multiple species at different trophic levels.
• Statement 3 is incorrect: A food chain shows energy transfer but does not quantify the exact number of organisms consumed.

Thus, only statement 1 is correct.

Q27. Which of the following organisms are used as biofertilizers?

[UPSC CSE Prelims 2014]

1. Agaricus
2. Nostoc
3. Spirogyra

Select the correct answer:

(a) 1 and 2
 (b) 2 only
 (c) 2 and 3
 (d) 3 only

Answer: (b)

Explanation:

• Nostoc is a nitrogen-fixing cyanobacterium that converts atmospheric nitrogen into a usable form for plants, making it an effective biofertilizer.
• Agaricus is a genus of mushrooms, not used as a biofertilizer.
• Spirogyra is a type of green algae that contributes to oxygen production but is not a biofertilizer.

Thus, Nostoc (option b) is the correct answer.

Q28. Which of the following contribute(s) nitrogen to the soil?

[UPSC CSE Prelims 2014]

1. Excretion of urea by animals
2. Burning of coal by humans
3. Death of vegetation

Select the correct answer:

(a) 1 only
 (b) 2 and 3 only
 (c) 1 and 3 only
 (d) 1, 2, and 3

Answer: (c)

Explanation:

• Statement 1 is correct: Urea contains nitrogen, and when animals excrete urea, it breaks down into ammonia, enriching the soil with nitrogen.
• Statement 2 is incorrect: Burning coal releases nitrogen oxides (NOx) into the air, but this does not directly add nitrogen to the soil.
• Statement 3 is correct: When plants die and decompose, nitrogen compounds are released into the soil, aiding plant growth.

Thus, excretion of urea and plant decomposition (statements 1 and 3) add nitrogen to the soil.

Q29. Which term refers not only to the physical space occupied by an organism but also to its functional role in an ecosystem?

[UPSC CSE Prelims 2014]

(a) Ecotone
 (b) Ecological niche
 (c) Habitat
 (d) Home range

Answer: (b)

Explanation:

• An ecological niche describes both where an organism lives (habitat) and how it interacts with its environment.
• It includes factors such as feeding habits, reproductive behavior, and interactions with other species.
• Habitat (option c) refers only to the physical location, whereas ecotone (option a) is a transition zone between two ecosystems.
• Home range (option d) is the area an animal typically moves within, but it does not define its ecological role.

Thus, the correct answer is ecological niche (option b).

ENVIRONMENTAL POLLUTION

Q1. Consider the following statements: [UPSC CSE Pre 2024]

Statement-I: Many chewing gums found in the market are considered a source of environmental pollution.
 Statement-II: Many chewing gums contain plastic as gum base.

Which one of the following is correct in respect of the above statements?

(a) Both Statement-I and Statement-II are correct, and Statement-II explains Statement-I
 (b) Both Statement-I and Statement-II are correct, but Statement-II does not explain Statement-I
 (c) Statement-I is correct, but Statement-II is incorrect
 (d) Statement-I is incorrect, but Statement-II is correct

Explanation:
 Modern chewing gum consists of four groups of ingredients that contribute to its texture, flavor, and elasticity:

1.    Fillers such as talc and calcium carbonate add bulk.

2.    Polymers (like polyvinyl acetate) provide stretch and form the "gum base."

3.    Emulsifiers help mix flavors and reduce stickiness.

4.    Softeners (such as vegetable oil) maintain chewiness.

Statement-I is correct because chewing gum is a significant source of environmental pollution. It is non-biodegradable and contributes to plastic waste that lingers in the environment for years.

Statement-II is also correct as many chewing gums contain polyvinyl acetate (PVA), a plastic-based substance used in manufacturing tires and glue. According to research, chewing gum generates over 105 tonnes of plastic waste annually, making it a severe environmental hazard.

Since the plastic content in chewing gum directly contributes to its role in pollution, Statement-II correctly explains Statement-I.

Thus, the correct answer is (a) Both Statement-I and Statement-II are correct, and Statement-II explains Statement-I

Q2. Consider the following: [UPSC CSE Pre 2024]

1. Battery storage
2. Biomass generators
3. Fuel cells
4. Rooftop solar photovoltaic units

How many of the above are considered "Distributed Energy Resources"?

(a) Only one
 (b) Only two
 (c) Only three
 (d) All four

Explanation:

• Distributed Energy Resources (DERs) are small-scale, decentralized energy sources that are typically located close to the end-user and provide power generation or storage.
• DERs can include renewable energy sources, battery storage, fuel cells, biomass generators, and rooftop solar units.

Analysis of the given options:

1. Battery storage – Yes, energy storage systems (ESS), including lithium-ion and other batteries, are DERs.
2. Biomass generators – Yes, small-scale biomass energy generation qualifies as a DER.
3. Fuel cells – Yes, hydrogen fuel cells, which generate electricity through chemical reactions, are part of DERs.
4. Rooftop solar photovoltaic units – Yes, one of the most common DERs.

Since all four options fall under DERs, the correct answer is:
 (d) All four.

Q3. With reference to perfluoroalkyl and polyfluoroalkyl substances (PFAS) that are used in making many consumer products, consider the following statements: (UPSC - 2024)

1. PFAS are found to be widespread in drinking water, food, and food packaging material.
2. PFAS are not easily degraded in the environment.
3. Persistent exposure to PFAS can lead to bioaccumulation in animal bodies.

Which of the statements given above are correct?

(a) 1 and 2 only
 (b) 2 and 3 only
 (c) 1 and 3 only
 (d) 1, 2 and 3

Explanation:

• Statement 1 is correct: PFAS are synthetic chemicals found in various consumer products, including food packaging, non-stick cookware, stain-resistant fabrics, and firefighting foams. Due to their widespread use, they have been detected in drinking water, food, and even human blood.
• Statement 2 is correct: PFAS are known as "forever chemicals" because they do not easily degrade in the environment. Their chemical structure makes them highly resistant to breakdown, leading to their persistent presence in soil, water, and air.
• Statement 3 is correct: PFAS accumulate in living organisms over time, as their excretion rate is slower than their intake. This bioaccumulation can have serious health effects, including potential risks of cancer, immune system disorders, and hormonal imbalances.

Since all three statements are correct, the correct answer is: (d) 1, 2 and 3.

Q4. Consider the following statements regarding mercury pollution: (UPSC CSE Prelims 2023)

1. Gold mining activity is a source of mercury pollution in the world.
2. Coal-based thermal power plants cause mercury pollution.
3. There is no known safe level of exposure to mercury.

How many of the above statements are correct?
 (a) Only one
 (b) Only two
 (c) All three
 (d) None

Solution: (c)

Explanation:

• Statement 1 is correct: Gold mining is a major source of mercury pollution, especially in regions like the Amazon. Miners use liquid mercury to bind with gold, but the process contaminates water bodies, leading to bioaccumulation in aquatic ecosystems.
• Statement 2 is correct: Coal-fired thermal power plants (TPPs) are one of the largest industrial sources of mercury emissions. Mercury is released into the atmosphere through fly ash, which often gets deposited in water bodies and soil.
• Statement 3 is correct: Mercury is a highly toxic element with no known safe level of exposure. Even small amounts can cause severe neurological, developmental, and organ damage, particularly in children and pregnant women.

Q5. Among the following crops, which one is the most important anthropogenic source of both methane and nitrous oxide? (UPSC CSE Prelims 2022)

(a) Cotton
 (b) Rice
 (c) Sugarcane
 (d) Wheat

Solution: (b)

Explanation:

• Rice cultivation is a significant source of both methane (CH₄) and nitrous oxide (N₂O), two potent greenhouse gases.
• Methane emissions occur in flooded rice fields due to anaerobic decomposition of organic matter. The absence of oxygen creates conditions that favor methane-producing bacteria.
• Nitrous oxide emissions arise from nitrogen fertilizers and microbial activity in the soil. The rice plant acts as a channel for the release of these gases into the atmosphere.
• Compared to other crops, rice contributes the most to global anthropogenic methane and nitrous oxide emissions.

Q6. In the context of WHO Air Quality Guidelines, consider the following statements: (UPSC CSE Prelims 2022)

1. The 24-hour mean of PM2.5 should not exceed 15 µg/m³ and the annual mean should not exceed 5 µg/m³.
2. In a year, the highest levels of ozone pollution occur during periods of inclement weather.
3. PM10 can penetrate the lung barrier and enter the bloodstream.
4. Excessive ozone in the air can trigger asthma.

Which of the statements given above are correct?
 (a) 1, 3, and 4
 (b) 1 and 4 only
 (c) 2, 3, and 4
 (d) 1 and 2 only

Solution: (a)

Explanation:

• Statement 1 is correct: The WHO Global Air Quality Guidelines (AQGs) recommend a 24-hour mean limit of 15 µg/m³ for PM2.5 and an annual mean limit of 5 µg/m³ to minimize health risks.
• Statement 2 is incorrect: Ozone pollution peaks during periods of strong sunlight due to photochemical reactions involving nitrogen oxides (NOx) and volatile organic compounds (VOCs), not during inclement weather.
• Statement 3 is incorrect: PM10 particles can enter the respiratory tract, but only 5 is small enough to penetrate the lung barrier and enter the bloodstream.
• Statement 4 is correct: Ozone is a major respiratory irritant that can trigger asthma, lung inflammation, and other respiratory diseases.

Q7. Consider the following: (UPSC CSE Prelims 2022)

1. Carbon monoxide
2. Nitrogen oxide
3. Ozone
4. Sulphur dioxide

Excess of which of the above in the environment is/are cause(s) of acid rain?
 (a) 1, 2, and 3
 (b) 2 and 4 only
 (c) 4 only
 (d) 1, 3, and 4

Solution: (b)

Explanation:

• Acid rain is primarily caused by the presence of sulphur dioxide (SO₂) and nitrogen oxides (NOx) in the atmosphere.
• These gases react with water, oxygen, and other chemicals to form sulfuric acid (H₂SO₄) and nitric acid (HNO₃), which then fall to the ground as acid rain.
• Carbon monoxide (CO) and ozone (O₃) do not contribute significantly to acid rain.

Q8. 'R2 Code of Practices' constitutes a tool available for promoting the adoption of

[UPSC CSE Pre 2021]
 (a) Environmentally responsible practices in the electronics recycling industry.
 (b) Ecological management of 'Wetlands of International Importance' under the Ramsar Convention.
 (c) Sustainable practices in the cultivation of agricultural crops in degraded lands.
 (d) Environmental Impact Assessment in the exploitation of natural resources.

Solution: (a)

Explanation:
The R2 Standard (Responsible Recycling Standard) is a globally recognized set of best practices for the electronics refurbishing and recycling industry. Developed by Sustainable Electronics Recycling International (SERI), it ensures environmental responsibility, worker health, and safety in handling electronic waste. The standard helps prevent improper disposal and promotes reuse, thereby minimizing environmental hazards.

Q9. Why is there a concern about copper smelting plants?

1. They may release lethal quantities of carbon monoxide into the environment.
2. The copper slag can cause the leaching of some heavy metals into the environment.
3. They may release sulfur dioxide as a pollutant.

Select the correct answer using the code given below:
 [UPSC CSE Pre 2021]
 (a) 1 and 2 only
 (b) 2 and 3 only
 (c) 1 and 3 only
 (d) 1, 2 and 3

Solution: (b)

Explanation:

• Statement 1 is incorrect. In the copper smelting process, carbon reacts with oxygen to form carbon monoxide (CO), but it does not release lethal quantities into the environment. Instead, CO is converted into carbon dioxide (CO₂) during the process.
• Statement 2 is correct. Copper slag contains heavy metals like lead, arsenic, and selenium, which can leach into soil and water, contaminating the environment.
• Statement 3 is correct. Copper smelters release sulfur dioxide (SO₂), a major pollutant contributing to acid rain and respiratory issues.

Q10. With reference to furnace oil, consider the following statements:

1. It is a product of oil refineries.
2. Some industries use it to generate power.
3. Its use causes sulfur emissions into the environment.

Which of the statements given above are correct?
 [UPSC CSE Pre 2021]
 (a) 1 and 2 only
 (b) 2 and 3 only
 (c) 1 and 3 only
 (d) 1, 2 and 3

Solution: (d)

Explanation:

• Statement 1 is correct. Furnace oil is a byproduct of crude oil refining, consisting of residual fuel oil that is left after distillation.
• Statement 2 is correct. Many industries use furnace oil in boilers, power plants, and industrial heating.
• Statement 3 is correct. Furnace oil has a high sulfur content, which, when burned, releases sulfur dioxide (SO₂), a pollutant responsible for acid rain and respiratory problems.

Q11. Magnetite particles, suspected to cause neurodegenerative problems, are generated as environmental pollutants from which of the following?

1. Brakes of motor vehicles
2. Engines of motor vehicles
3. Microwave stoves within homes
4. Power plants
5. Telephone lines

Select the correct answer using the code given below:
 [UPSC CSE Pre 2021]
 (a) 1, 2, 3 and 5 only
 (b) 1, 2 and 4 only
 (c) 3, 4 and 5 only
 (d) 1, 2, 3, 4 and 5

Solution: (b)

Explanation:

• Magnetite particles are tiny iron oxide pollutants that can enter the bloodstream and affect the brain, potentially leading to neurodegenerative diseases like Alzheimer’s.
• Option 1 is correct. Brake pads release magnetite particles due to friction.
• Option 2 is correct. Engines generate magnetite due to combustion and high-temperature processes.
• Option 3 is incorrect. Microwave stoves do not generate significant magnetite particles.
• Option 4 is correct. Coal-based power plants release magnetite during combustion.
• Option 5 is incorrect. Telephone lines do not emit magnetite particles as they carry low-frequency signals.

Q12. Bisphenol A (BPA), a cause of concern, is a structural/key component in the manufacture of which of the following kinds of plastics?

[UPSC CSE Pre 2021]
 (a) Low-density polyethylene
 (b) Polycarbonate
 (c) Polyethylene terephthalate
 (d) Polyvinyl chloride

Solution: (b)

Explanation:

• Bisphenol A (BPA) is a chemical used in the production of polycarbonate plastics and epoxy resins.
• Uses of Polycarbonate Plastics: Found in baby bottles, water bottles, food containers, and electronic devices.
• Health Concerns: BPA can leach into food and beverages, especially when heated, leading to hormonal disruptions and potential health risks.

Q13. 'Triclosan', considered harmful when exposed to high levels for a long time, is most likely present in which of the following?

[UPSC CSE Pre 2021]
 (a) Food preservatives
 (b) Fruit-ripening substances
 (c) Reused plastic containers
 (d) Toiletries

Solution: (d)

Explanation:

• Triclosan is a chemical used in antibacterial soaps, toothpaste, and personal care products.
• Health Concerns: Prolonged exposure is linked to antibiotic resistance, endocrine disruption, and thyroid hormone imbalances.

Q14. According to India's National Policy on Biofuels, which of the following can be used as raw materials for the production of biofuels?

[UPSC CSE Pre 2020]

1. Cassava
2. Damaged wheat grains
3. Groundnut seeds
4. Horse grams
5. Rotten potatoes
6. Sugar beet

Select the correct answer using the code given below:
 (a) 1, 2, 5 and 6 only
 (b) 1, 3, 4 and 6 only
 (c) 2, 3, 4 and 5 only
 (d) 1, 2, 3, 4, 5 and 6

Solution: (a)

Explanation:

• The National Policy on Biofuels (2018) promotes biofuel production using non-food feedstock.
• Approved raw materials: Cassava, damaged wheat grains, rotten potatoes, and sugar beet.
• Groundnut seeds and horse grams are not used for biofuel production.

Q15. Consider the following statements:

[UPSC CSE Pre 2020]

1. Coal ash contains arsenic, lead, and mercury.
2. Coal-fired power plants release sulfur dioxide and oxides of nitrogen into the environment.
3. High ash content is observed in Indian coal.

Which of the statements given above is/are correct?
 (a) 1 only
 (b) 2 and 3 only
 (c) 3 only
 (d) 1, 2 and 3

Solution: (d)

Explanation:

• Statement 1 is correct. Coal ash contains toxic heavy metals like arsenic, lead, and mercury.
• Statement 2 is correct. Coal-fired power plants emit sulfur dioxide (SO₂) and nitrogen oxides (NOx), causing air pollution.
• Statement 3 is correct. Indian coal has a high ash content (40-45%), making it less efficient and more polluting.

Q16 (2020): Which of the following are the reasons/factors for exposure to benzene pollution?

1. Automobile exhaust
2. Tobacco smoke
3. Wood burning
4. Using varnished wooden furniture
5. Using products made of polyurethane

Select the correct answer using the code given below:
(a) 1, 2, and 3 only
(b) 2 and 4 only
(c) 1, 3, and 4 only
(d) 1, 2, 3, 4, and 5

Answer: (a)
Explanation: Benzene is a colorless liquid with a sweet odor, highly flammable, and volatile, leading to inhalation exposure. It is associated with severe health effects, including cancer and aplastic anemia.

• Correct: Automobile exhaust (1), tobacco smoke (2), and wood burning (3) are significant sources of benzene pollution.
• Incorrect: Varnished wooden furniture (4) and polyurethane products (5) may contain benzene but are not major contributors.

Q17 (2011): Consider the following statements:

1. Agricultural soils release nitrogen oxides into the environment.
2. Cattle release ammonia into the environment.
3. Poultry industry releases reactive nitrogen compounds into the environment.

Which of the statements given above is/are correct?
(a) 1 and 3 only
(b) 2 and 3 only
(c) 2 only
(d) 1, 2, and 3

Answer: (d)
Explanation:

• Statement 1: Agricultural soils emit nitrogen oxides due to nitrification and denitrification processes.
• Statement 2: Cattle release ammonia through urine and feces, contributing to air pollution.
• Statement 3: The poultry industry emits ammonia, nitrous oxide, and nitrogen dioxide through manure management and feed practices.

Q18 (2019): Why is there a great concern about microbeads in the environment?
(a) They are harmful to marine ecosystems.
(b) They cause skin cancer in children.
(c) They are absorbed by crop plants in irrigated fields.
(d) They are used as food adulterants.

Answer: (a)
Explanation: Microbeads are plastic particles (<1mm) found in cosmetics, exfoliants, and cleaning products. They do not biodegrade and accumulate in aquatic environments, harming marine life.

Q19 (2020): Which of the following are released due to crop/biomass residue burning?

1. Carbon monoxide
2. Methane
3. Ozone
4. Sulfur dioxide

Select the correct answer using the code given below:
(a) 1 and 2 only
(b) 2, 3, and 4 only
(c) 1 and 4 only
(d) 1, 2, 3, and 4

Answer: (d)
Explanation: Burning crop residues releases multiple pollutants, including CO, CH4, O3, and SO2, contributing to severe air quality degradation.

Q20 (2019): The terms 'pyrolysis and plasma gasification' are related to:
(a) Extraction of rare earth elements
(b) Natural gas extraction technologies
(c) Hydrogen fuel-based automobiles
(d) Waste-to-energy technologies

Answer: (d)
Explanation:

• Pyrolysis: Thermal decomposition of organic material in the absence of oxygen.
• Plasma Gasification: High-temperature process converting waste into synthesis gas (H2 + CO), useful for energy production.

Q21(2020): Regarding H-CNG as fuel, consider the following statements:

1. It eliminates carbon monoxide emissions.
2. It reduces CO2 and hydrocarbon emissions.
3. Up to one-fifth hydrogen can be blended with CNG.
4. H-CNG is cheaper than CNG.

Which statements are correct?
(a) 1 only
(b) 2 and 3 only
(c) 4 only
(d) 1, 2, 3, and 4

Answer: (b)
Explanation: H-CNG reduces but does not eliminate CO emissions. It improves combustion efficiency and reduces pollutants. However, hydrogen production costs make it more expensive than CNG.

Q22 (2019): Which of the following statements about methane hydrate deposits are correct?

1. Global warming may trigger methane release from these deposits.
2. Large methane hydrate deposits exist in the Arctic tundra and seafloor.
3. Atmospheric methane oxidizes to CO2 in a decade or two.

Select the correct answer using the code below:
(a) 1 and 2 only
(b) 2 and 3 only
(c) 1 and 3 only
(d) 1, 2, and 3

Answer: (d)
Explanation:

• Methane hydrates are stable at low temperatures/high pressures. Global warming can cause their dissociation.
• They are found in Arctic permafrost and deep-sea sediments.
• Methane oxidizes to CO2 over decades, not instantly.

Q23 (2018): Possible consequences of heavy sand mining in riverbeds:

1. Decreased salinity in the river
2. Pollution of groundwater
3. Lowering of the water table

Select the correct answer:
(a) 1 only
(b) 2 and 3 only
(c) 1 and 3 only
(d) 1, 2, and 3

Answer: (b)
Explanation: Sand mining does not reduce salinity but can lower water tables and pollute groundwater by disturbing aquifers.

Q24 (2021): Limitations of algae-based biofuels in developing countries:

1. Production is only possible in seas, not on continents.
2. Setting up facilities requires advanced technology.
3. Large-scale production raises ecological/social concerns.

Select the correct answer:
(a) 1 and 2 only
(b) 2 and 3 only
(c) 3 only
(d) 1, 2, and 3

Answer: (b)
Explanation: Algae can be cultivated in different environments, not just seas. However, infrastructure and scale-related concerns limit their adoption in developing countries.

Q25 (2017): In the context of solving pollution problems, what is/are the advantage(s) of the bioremediation technique?

1. It is a technique for cleaning up pollution by enhancing the same biodegradation process that occurs in nature.
2. Any contaminant with heavy metals such as cadmium and lead can be readily and completely treated by bioremediation using microorganisms.
3. Genetic engineering can be used to create microorganisms specifically designed for bioremediation.

Select the correct answer using the code given below:
(a) 1 only
(b) 2 and 3 only
(c) 1 and 3 only
(d) 1, 2, and 3

Answer: (c)
Explanation:

• Statement 1: Bioremediation enhances the natural biodegradation process using microorganisms, plants, or enzymes to detoxify contaminants in soil and water.
• Statement 2: While bioremediation is effective for many pollutants, heavy metals like cadmium and lead are not readily absorbed or broken down by microorganisms.
• Statement 3: Genetic engineering enables the development of specialized microorganisms for bioremediation, capable of degrading specific pollutants like oil and pesticides.

Q26 (2014): There is concern regarding nanoparticles of some chemical elements used in industries. Why?

1. They can accumulate in the environment and contaminate water and soil.
2. They can enter the food chains.
3. They can trigger the production of free radicals.

Select the correct answer using the code given below:
(a) 1 and 2 only
(b) 3 only
(c) 1 and 3 only
(d) 1, 2, and 3

Answer: (d)
Explanation:

• Statement 1: Nanoparticles are extremely small and can easily move through the environment, leading to their accumulation in water and soil.
• Statement 2: These particles can enter food chains through plants and animals, and they can also be absorbed into the bloodstream via skin or lungs.
• Statement 3: Nanoparticles may trigger the production of free radicals, which can damage cells and contribute to diseases such as cancer, heart disease, and Alzheimer’s.

Key Insight: Nanomaterials can cross biological membranes, reaching cells, tissues, and organs that larger particles cannot access.

Q27 (2014): Why is there concern about brominated flame retardants (BFRs)?

1. They are highly resistant to degradation in the environment.
2. They are able to accumulate in humans and animals.

Select the correct answer using the code given below:
(a) 1 only
(b) 2 only
(c) Both 1 and 2
(d) Neither 1 nor 2

Answer: (c)
Explanation:

• Statement 1: BFRs are highly resistant to degradation and persist in the environment for long periods.
• Statement 2: They bioaccumulate in humans and animals, entering the body through food, water, and air.

Key Insight: BFRs, commonly found in plastics, textiles, and electronic equipment, are environmental pollutants that pose serious health risks due to their persistence and bioaccumulative properties.

Q28 (2014): With reference to the Neem tree, consider the following statements:

1. Neem oil can be used as a pesticide to control the proliferation of some species of insects and mites.
2. Neem seeds are used in the manufacture of biofuels and hospital detergents.
3. Neem oil has applications in the pharmaceutical industry.

Which of the statements given above is/are correct?
(a) 1 and 2 only
(b) 3 only
(c) 1 and 3 only
(d) 1, 2, and 3

Answer: (d)
Explanation:

• Statement 1: Neem oil is a natural pesticide effective against various pests, including aphids, whiteflies, and spider mites.
• Statement 2: Neem seeds contain oil used in biofuel production and hospital detergents due to their antibacterial properties.
• Statement 3: Neem oil is widely used in pharmaceuticals for treating skin conditions, malaria, and bacterial infections.

Key Insight: Neem oil disrupts insect behavior and hormonal systems, making it a sustainable pest control solution.

Q29 (2014): With reference to the usefulness of sugar industry by-products, which statements are correct?

1. Bagasse can be used as biomass fuel for the generation of energy.
2. Molasses can be used as one of the feedstocks for the production of synthetic chemical fertilizers.
3. Molasses can be used for the production of ethanol.

Select the correct answer using the codes given below:
(a) 1 only
(b) 2 and 3 only
(c) 1 and 3 only
(d) 1, 2, and 3

Answer: (c)
Explanation:

• Statement 1: Bagasse, a fibrous residue from sugarcane, is used as a biomass fuel for energy production.
• Statement 2: Molasses contains nutrients but is not used for synthetic chemical fertilizers.
• Statement 3: Molasses can be fermented to produce ethanol, a biofuel used as an additive in gasoline.

Key Insight: The sugar industry generates multiple useful by-products that contribute to renewable energy and industrial applications.

BIODIVERSITY

Q1. Consider the following statements: [UPSC CSE Pre]

1. Lions do not have a particular breeding season.
2. Unlike most other big cats, cheetahs do not roar.
3. Unlike male lions, male leopards do not proclaim their territory by scent marking.

Which of the statements given above are correct?

(a) 1 and 2 only
 (b) 2 and 3 only
 (c) 1 and 3 only
 (d) 1, 2 and 3

Explanation:

• Statement 1 is correct: Lions do not have a fixed breeding season. Breeding can occur year-round, though it often synchronizes within a pride, especially after a pride takeover, allowing communal raising of cubs.
• Statement 2 is correct: Cheetahs, unlike most other big cats, do not roar. Their vocal cords are structured differently, allowing them to purr continuously but preventing them from roaring. Instead, they produce sounds like chirps, growls, and yelps for communication.
• Statement 3 is incorrect: Male leopards do scent-mark their territory, similar to lions. They use urine, feces, cheek rubbing on trees, and scrape markings on the ground or logs to establish territorial boundaries and communicate with other leopards.

Thus, the correct answer is (a) 1 and 2 only.

Q2 (2023): Consider the following statements:

Statement I: Marsupials are not naturally found in India.
Statement II: Marsupials can thrive only in montane grasslands with no predators.

Which one of the following is correct in respect of the above statements?
(a) Both Statement-I and Statement-II are correct, and Statement-II is the correct explanation for Statement-I.
(b) Both Statement-I and Statement-II are correct, but Statement-II is not the correct explanation for Statement-I.
(c) Statement-I is correct, but Statement-II is incorrect.
(d) Statement-I is incorrect, but Statement-II is correct.

Answer: (c)
Explanation:

• Statement I is correct: Marsupials are found in Australia, Papua New Guinea, and South America, but not naturally in India. Examples include kangaroos, wallabies, and opossums.
• Statement II is incorrect: Marsupials can thrive in various habitats, including rainforests, forests, and even underground (e.g., wombats burrow underground).

Q3 (2023): Consider the following fauna:

1. Lion-tailed Macaque
2. Malabar Civet
3. Sambar Deer

How many of the above are generally nocturnal or most active after sunset?
(a) Only one
(b) Only two
(c) All three
(d) None

Answer: (b)
Explanation:

• Lion-tailed Macaque: Diurnal (active during the day).
• Malabar Civet: Nocturnal, endemic to the Western Ghats.
• Sambar Deer: Crepuscular and nocturnal, most active at dusk and night.

Thus, two of them are nocturnal.

Q4 (2023): Which of the following organisms perform waggle dance for others of their kin to indicate the direction and distance to a food source?
(a) Butterflies
(b) Dragonflies
(c) Honeybees
(d) Wasps

Answer: (c)
Explanation:
Honeybees perform two types of dances:

• Round Dance: For food sources within 25-100 meters, without direction cues.
• Waggle Dance: For food sources farther away, providing directional and distance cues through body movement patterns.

Q5 (2023): Consider the following statements regarding mushrooms:

1. Some have medicinal properties.
2. Some have psychoactive properties.
3. Some have insecticidal properties.
4. Some have bioluminescent properties.

How many of the above statements are correct?
(a) Only one
(b) Only two
(c) Only three
(d) All four

Answer: (d)
Explanation:

• Medicinal mushrooms: Shiitake, maitake, and reishi have anti-tumor and immune-boosting properties.
• Psychoactive mushrooms: Contain psilocybin, causing hallucinations.
• Insecticidal mushrooms: Some species have natural insect-repellent compounds.
• Bioluminescent mushrooms: Found in Northeast India, such as Roridomyces phyllostachydis.

Q6 (2023): Consider the following statements regarding Indian squirrels:

1. They build nests by making burrows in the ground.
2. They store food materials like nuts and seeds in the ground.
3. They are omnivorous.

How many of the above statements are correct?
(a) Only one
(b) Only two
(c) All three
(d) None

Answer: (b)
Explanation:

• Statement 1 is incorrect: Indian squirrels build nests in trees, not burrows.
• Statement 2 is correct: They store food underground for later use.
• Statement 3 is correct: They are omnivores, consuming fungi, seeds, fruits, and occasionally insects or eggs.

Q7 (2023):Consider the following statements:

1. Some microorganisms can grow in environments with temperatures above the boiling point of water.
2. Some microorganisms can grow in environments with temperatures below the freezing point of water.
3. Some microorganisms can grow in highly acidic environments with a pH below 3.

How many of the above statements are correct?
(a) Only one
(b) Only two
(c) All three
(d) None

Answer: (c)
Explanation:

• Statement 1 is correct: Thermophiles, like Pyrolobus fumarii, thrive in environments exceeding 100°C, such as hydrothermal vents.
• Statement 2 is correct: Psychrophiles, such as Cryobacterium, can survive in sub-zero temperatures, including polar ice caps.
• Statement 3 is correct: Acidophiles, such as Acidithiobacillus ferrooxidans, can thrive in extreme acidity with pH levels below 3.

Q8 (2023): Which one of the following animals makes a tool with a stick to scrape insects from a hole in a tree or a log of wood?

(a) Fishing cat
(b) Orangutan
(c) Otter
(d) Sloth bear

Answer: (b)
Explanation:

• Orangutans are known for their advanced tool-making abilities. They use sticks to extract termites and insects from trees and logs, demonstrating intelligence and adaptability.

Q9 (2022):With reference to "Gucchi," sometimes mentioned in the news, consider the following statements:

1. It is a fungus.
2. It grows in some Himalayan forest areas.
3. It is commercially cultivated in the Himalayan foothills of northeastern India.

Which of the statements given above is/are correct?
(a) 1 only
(b) 3 only
(c) 1 and 2 only
(d) 2 and 3 only

Answer: (c)
Explanation:

• Statement 1 is correct: Gucchi mushroom (Morchella esculenta) is a species of fungus from the family Morchellaceae.
• Statement 2 is correct: It grows naturally in the Himalayan foothills of Himachal Pradesh, Uttarakhand, and Jammu & Kashmir.
• Statement 3 is incorrect: Gucchi mushrooms cannot be commercially cultivated; they grow naturally in conifer forests.

Q10 (2022): Which of the following is not a bird?
(a) Golden Mahseer
(b) Indian Nightjar
(c) Spoonbill
(d) White Ibis

Answer: (a)
Explanation:

• Golden Mahseer is a freshwater fish species, not a bird. It inhabits fast-moving hill streams and rivers in the Himalayan and peninsular river systems.
• Indian Nightjar, Spoonbill, and White Ibis are all bird species.

Q11 (2022):"Biorock technology" is associated with which one of the following situations?

(a) Restoration of damaged coral reefs
(b) Development of building materials using plant residues
(c) Identification of areas for exploration/extraction of shale gas
(d) Providing salt licks for wild animals in forests/protected areas

Answer: (a)
Explanation:

• Biorock technology involves using electro-accumulation of minerals to enhance coral reef restoration.
• A mild electrical current is passed through submerged metal structures, promoting the deposition of calcium carbonate, which facilitates coral growth.
• This method has been used successfully in the Gulf of Kachchh, India.

Q12 (2022):The "Miyawaki method" is well known for:

(a) Promotion of commercial farming in arid and semi-arid areas
(b) Development of gardens using genetically modified flora
(c) Creation of mini forests in urban areas
(d) Harvesting wind energy on coastal areas and on sea surfaces

Answer: (c)
Explanation:

• The Miyawaki method, developed by Japanese botanist Akira Miyawaki, is a technique for afforestation in urban areas.
• It involves planting native tree species at high density, allowing forests to grow faster and become self-sustaining.
• The Bombay Municipal Corporation (BMC) has implemented this method to create urban forests in Mumbai.

Q13. Certain species of which among the following organisms are well known for their ability to cultivate fungi?(UPSC CSE Prelims 2022)
 (a) Ant
 (b) Cockroach
 (c) Crab
 (d) Spider

Solution: (a)
 Explanation: Certain species of ants, commonly referred to as "fungus-growing ants," exhibit a unique symbiotic relationship with fungi. These ants cultivate fungi within their nests, which serves as their primary food source. This mutualistic association is particularly observed in species found across the American continents and the West Indies.

Q14. In nature, which of the following organisms are most likely to survive on a surface without soil? (UPSC CSE Prelims 2021)

1. Fern
2. Lichen
3. Moss
4. Mushroom

Select the correct answer using the code below:
 (a) 1 and 4 only
 (b) 2 only
 (c) 2 and 3 only
 (d) 1, 3, and 4 only

Solution: (c)
 Explanation:

• Lichens can thrive on a variety of surfaces, including trees, rocks, and artificial structures. They do not require soil for growth.
• Mosses are non-vascular plants that absorb water and nutrients from the atmosphere rather than relying on soil. They often grow on rocks and tree trunks.
• Ferns, however, are vascular plants that require soil for growth.
• Mushrooms typically grow on decaying organic matter or soil, making them less likely to thrive in a completely soil-free environment.

Q15.Which among the following is commonly used in preparing a natural mosquito repellent? (UPSC CSE Prelims 2021)

(a) Congress grass
 (b) Elephant grass
 (c) Lemongrass
 (d) Nut grass

Solution: (c)
 Explanation:
 Lemongrass contains citronella, a compound known for its strong mosquito-repelling properties. The intense aroma of lemongrass oil is effective in masking the scents that attract mosquitoes, making it a popular choice for natural repellents.

Q16. Consider the following groups of organisms: (UPSC CSE Prelims 2021)

1. Copepods
2. Cyanobacteria
3. Diatoms
4. Foraminifera

Which of the above are primary producers in oceanic food chains?

(a) 1 and 2
 (b) 2 and 3
 (c) 3 and 4
 (d) 1 and 4

Solution: (b)
 Explanation:

• Cyanobacteria (blue-green algae) are photosynthetic organisms that play a crucial role as primary producers in marine ecosystems.
• Diatoms are microscopic algae that carry out photosynthesis and contribute significantly to global oxygen production.
• Copepods are not primary producers; they are zooplankton that feed on phytoplankton.
• Foraminifera are heterotrophic organisms that consume smaller organisms and organic matter.

Q17.Consider the following animals: (UPSC CSE Prelims 2021)

1. Hedgehog
2. Marmot
3. Pangolin

Which of the above roll(s) up to protect vulnerable body parts from predators?

(a) 1 and 2 only
 (b) 2 only
 (c) 3 only
 (d) 1 and 3 only

Solution: (d)
 Explanation:

• Hedgehogs curl up into a ball, exposing only their spines when threatened. This defense mechanism helps them deter predators.
• Pangolins are covered in tough scales and roll into a tight ball when under threat, making them difficult for predators to attack.
• Marmots, on the other hand, do not use rolling as a defense mechanism.

Q18. Which among the following is classified as a filter feeder? (UPSC CSE Prelims 2021)

(a) Catfish
 (b) Octopus
 (c) Oyster
 (d) Pelican

Solution: (c)
 Explanation:
 Oysters are filter feeders that extract plankton and organic particles from the water. Their gills function as natural filters, removing particles as small as 4 micrometers. Unlike oysters, catfish, octopuses, and pelicans rely on different feeding strategies, such as active hunting or scavenging.

Q19. With reference to Indian elephants, consider the following statements: (UPSC CSE Prelims 2020)

1. The leader of an elephant herd is always a female.
2. The maximum gestation period of an elephant can be 22 months.
3. An elephant can give birth only until the age of 40 years.
4. Among Indian states, Kerala has the highest elephant population.

Which of the statements given above are correct?

(a) 1 and 2 only
 (b) 2 and 4 only
 (c) 3 only
 (d) 1, 3, and 4 only

Solution: (a)
 Explanation:

• Statement 1 is correct. Elephant herds are matriarchal, meaning they are led by the oldest and most experienced female.
• Statement 2 is correct. The gestation period of an elephant is the longest among mammals, reaching up to 22 months.
• Statement 3 is incorrect. Elephants can continue giving birth well beyond 40 years, with some calving until their 60s.
• Statement 4 is incorrect. Karnataka, not Kerala, has the highest elephant population in India.

Q20. Which one of the following protected areas is well-known for the conservation of a sub-species of the Indian swamp deer (Barasinga) that thrives well in hard ground and is exclusively graminivorous? (UPSC CSE Prelims 2020)
(a) Kanha National Park
(b) Manas National Park
 (c) Mudumalai Wildlife Sanctuary
 (d) Tal Chhapar Wildlife Sanctuary

Solution: (a)
 Explanation:
 Hard ground Indian swamp deer (Barasingha or Rucervus duvaucelii), the state animal of Madhya Pradesh, has seen a revival in the Kanha National Park and Tiger Reserve (KNPTR) after having been perilously close to extinction for a long time. KNPTR is on the Maikal range of the Satpura hills and is spread over an area of 940 square kilometers between Mandia and Balaghat districts of Madhya Pradesh. The swamp deer is endemic to KNPTR.

In 1967, the numbers of swamp deer decreased to 66 due to rampant hunting, habitat loss, and diseases. The number was estimated at around 551 in 1953. The deer was brought back from the verge of extinction with the help of a successful breeding program and conservation practices at the KNPTR. Various conservation methods were used, including habitat improvement and captive breeding, which led to an increase in the population to around 450 in 2015 and 800 in 2020.

Q21.If a particular plant species is placed under Schedule VI of The Wildlife Protection Act, 1972, what is the implication? (UPSC CSE Prelims 2020)
(a) A license is required to cultivate that plant.
(b) Such a plant cannot be cultivated under any circumstances.
 (c) It is a Genetically Modified crop plant.
 (d) Such a plant is invasive and harmful to the ecosystem.

Solution: (a)
 Explanation:
 If a particular plant species is placed under Schedule VI of The Wildlife Protection Act, 1972, then no person is allowed to cultivate the specified plant, except with a license granted by the Chief Wildlife Warden. The specified endemic plants in Schedule VI are prohibited from cultivation and planting, except with a granted license.

The plants mentioned in the sixth schedule are:

• Beddome’s cycad
• Blue Vanda
• Kuth
• Ladies’ slipper orchids
• Pitcher plant
• Red Vanda

Q22.With reference to India's biodiversity, Ceylon frogmouth, Coppersmith barbet, Gray-chinned minivet, and White-throated redstart are (UPSC CSE Prelims 2020)
(a) Birds
(b) Primates
 (c) Reptiles
 (d) Amphibians

Solution: (a)
 Explanation:
 Ceylon frogmouth, Coppersmith barbet, Gray-chinned minivet, and White-throated redstart are names of bird varieties found in India.

Q23. Consider the following States: (UPSC CSE Prelims 2019)

1. Chhattisgarh
2. Madhya Pradesh
3. Maharashtra
4. Odisha

With reference to the States mentioned above, in terms of percentage of forest cover to the total area of the State, which one of the following is the correct ascending order?
 (a) 2-3-1-4
 (b) 2-3-4-1
 (c) 3-2-4-1
 (d) 3-2-1-4

Solution: (c)
 Explanation:
 The ascending order of the states in terms of percentage of forest cover to the total area of the state is:
 Maharashtra (16.51%) < Madhya Pradesh (25.41%) < Odisha (33.5%) < Chhattisgarh (41.21%)

Q24.Consider the following statements: (UPSC CSE Prelims 2019)

1. Asiatic lion is naturally found in India only.
2. Double-humped camel is naturally found in India only.
3. One-horned rhinoceros is naturally found in India only.

Which of the statements given above is/are correct?
 (a) 1 only
 (b) 2 only
 (c) 1 and 3 only
 (d) 1, 2, and 3

Solution: (a)
 Explanation:
 The Asiatic lion is found only in India, specifically in Gir Forest, Gujarat. However, the double-humped camel is native to the steppes region of Central Asia and is also found in Ladakh, India. The one-horned rhinoceros is found not only in Assam’s Kaziranga National Park but also in Nepal’s Chitwan National Park.

Q25. Consider the following pairs: (UPSC CSE Prelims 2019)

Wildlife	Naturally found in
Blue-finned Mahseer	Cauvery River
Irrawaddy Dolphin	Chambal River
Rusty-spotted Cat	Eastern Ghats

Which of the pairs given above are correctly matched?
 (a) 1 and 2 only
 (b) 2 and 3 only
 (c) 1 and 3 only
 (d) 1, 2, and 3

Solution: (c)
 Explanation:
 Irrawaddy Dolphin is not found in the Chambal River. It is usually found near sea coasts and in estuaries and rivers in parts of the Bay of Bengal and Southeast Asia, including Chilika Lake (Odisha).

Q26. As per the Solid Waste Management Rules, 2016 in India, which one of the following statements is correct? (UPSC CSE Prelims 2019)
(a) Waste generator has to segregate the waste into five categories.
(b) The Rules are applicable to notified urban local bodies, notified towns, and all industrial townships only.
 (c) The Rules provide for exact and elaborate criteria for the identification of sites for landfills and waste processing facilities.
 (d) It is mandatory on the part of the waste generator that the waste generated in one district cannot be moved to another district.

Solution: (c)
 Explanation:
 Solid Waste Management Rules, 2016 provide for exact and elaborate criteria for the identification of sites for landfills and waste processing facilities.

Q27. Consider the following statements: (UPSC CSE Prelims 2019)

The Environment Protection Act, 1986 empowers the Government of India to:

1. State the requirement of public participation in the process of environmental protection, and the procedure and manner in which it is sought.
2. Lay down the standards for emission or discharge of environmental pollutants from various sources.

Which of the statements given above is/are correct?
 (a) 1 only
 (b) 2 only
 (c) Both 1 and 2
 (d) Neither 1 nor 2

Solution: (b)
 Explanation:
 Statement 1 is incorrect. The Environment Protection Act, 1986 does not contain any provision related to public participation.

Statement 2 is correct: As per Section 3 of the Environment Protection Act, the Government of India is empowered to make rules in laying down standards for emission or discharge of environmental pollutants from various sources.

Q28.Consider the following statements: (UPSC CSE Prelims 2019)

1. As per the recent amendment to the Indian Forest Act, 1927, forest dwellers have the right to fell the bamboos grown on forest areas.
2. As per the Scheduled Tribes and Other Traditional Forest Dwellers (Recognition of Forest Rights) Act, 2006, bamboo is a minor forest produce.
3. The Scheduled Tribes and Other Traditional Forest Dwellers (Recognition of Forest Rights) Act, 2006, allows ownership of minor forest produce to forest dwellers.

Which of the statements given above is/are correct?
 (a) 1 and 2 only
 (b) 2 and 3 only
 (c) 3 only
 (d) 1, 2, and 3

Solution: (b)
 Explanation:
 As per the recent amendment to the Indian Forest Act, 1927, forest dwellers have the right to fell bamboos grown on non-forest areas, not on forest lands. Bamboo is classified as a minor forest produce under the Scheduled Tribes and Other Traditional Forest Dwellers (Recognition of Forest Rights) Act, 2006, which allows forest dwellers ownership rights over such produce.

Q29. Consider the following statements: (UPSC CSE Prelims 2019)

1. As per law, the Compensatory Afforestation Fund Management and Planning Authority exists at both National and State levels.
2. People's participation is mandatory in the compensatory afforestation programmes carried out under the Compensatory Afforestation Fund Act, 2016.

Which of the statements given above is/are correct?
 (a) 1 only
 (b) 2 only
 (c) Both 1 and 2
 (d) Neither 1 nor 2

Solution: (a)
 Explanation:
 The Compensatory Afforestation Fund Management and Planning Authority (CAMPA) exists at both national and state levels. However, the Act does not mandate public participation in compensatory afforestation programmes—it only encourages it.

Q30. In India, 'Extended Producer Responsibility' was introduced as an important feature in which of the following? (UPSC CSE Prelims 2019)
(a) The Bio-medical Waste (Management and Handling) Rules, 1998
(b) The Recycled Plastic (Manufacturing and Usage) Rules, 1999
 (c) The e-Waste (Management and Handling) Rules, 2011
 (d) The Food Safety and Standard Regulations, 2011

Solution: (c)
 Explanation:
 Extended Producer Responsibility (EPR) was introduced in the e-Waste (Management and Handling) Rules, 2011. Under EPR, the producer of electrical or electronic equipment is responsible for ensuring the environmentally safe disposal of their products after consumers discard them.

Q31. Consider the following statements: (UPSC CSE Prelims 2018)

1. The definition of "Critical Wildlife Habitat" is incorporated in the Forest Rights Act, 2006.
2. For the first time in India, Baigas have been given Habitat Rights.
3. The Union Ministry of Environment, Forest and Climate Change officially decides and declares Habitat Rights for Primitive and Vulnerable Tribal Groups in any part of India.

Which of the statements given above is/are correct?
 (a) 1 and 2 only
 (b) 2 and 3 only
 (c) 3 only
 (d) 1, 2, and 3

Solution: (a)
 Explanation:
 The Forest Rights Act, 2006, defines "Critical Wildlife Habitat" to designate areas that require stricter conservation. The Baiga tribe in Madhya Pradesh and Chhattisgarh became the first community in India to receive habitat rights. However, the authority to declare habitat rights lies with the District Level Committee, not the Ministry of Environment, Forest and Climate Change.

Q32. Why is a plant called Prosopis juliflora often mentioned in news? (UPSC CSE Prelims 2018)
(a) Its extract is widely used in cosmetics.
(b) It tends to reduce biodiversity in the area in which it grows.
 (c) Its extract is used in the synthesis of pesticides.
 (d) None of these

Solution: (b)
 Explanation:
 Prosopis juliflora, an exotic species from South and Central America, is one of the most invasive species in India. Initially introduced to meet the rural fuelwood demand and restore degraded lands, it has spread aggressively, reducing biodiversity by outcompeting native species.

Q33. If you want to see gharials in their natural habitat, which one of the following is the best place to visit? (UPSC CSE Prelims 2017)
(a) Bhitarkanika Mangroves
(b) Chambal River
 (c) Pulicat Lake
 (d) Deepor Beel

Solution: (b)
 Explanation:
 The National Chambal Gharial Wildlife Sanctuary, located along the Chambal River, is a protected area for critically endangered gharials. Established in 1975, it plays a crucial role in their conservation.

Q34. In which of the following regions of India are you most likely to come across the 'Great Indian Hornbill' in its natural habitat? (UPSC CSE Prelims 2016)
(a) Sand deserts of northwest India
(b) Higher Himalayas of Jammu and Kashmir
 (c) Salt marshes of western Gujarat
 (d) Western Ghats

Solution: (d)
 Explanation:
 The Great Indian Hornbill is primarily found in the forests of the Western Ghats and the Nilgiris. It is a large frugivorous bird but also preys on small mammals, reptiles, and birds. The species' highest densities are found in the Nilgiri Biosphere Reserve.

Q35. Consider the following statements: (UPSC CSE Pre. 2016)

1. Kharai camels are capable of swimming up to three kilometres in seawater.
2. They survive by grazing on mangroves.
3. They live in the wild and cannot be domesticated.

Which of the statements given above is/are correct?
 (a) 1 and 2 only
 (b) 3 only
 (c) 1 and 3 only
 (d) 1, 2 and 3

Solution: (a)

Explanation:
 Kharai camels are known for their ability to swim in seawater and graze on mangroves, making them unique among camel breeds. Gujarat is the only state in India where these camels are found. However, they can be domesticated and provide livelihood support to nomadic communities like the Jats and Rabaris.

Q36. With reference to ‘Red Sanders’, sometimes seen in the news, consider the following statements: (UPSC CSE Pre. 2016)

1. It is a tree species found in a part of South India.
2. It is one of the most important trees in the tropical rainforest areas of South India.

Which of the statements given above is/are correct?
 (a) 1 only
 (b) 2 only
 (c) Both 1 and 2
 (d) Neither 1 nor 2

Solution: (a)

Explanation:
 Red Sanders is a non-fragrant variety of sandalwood that grows mainly in the deciduous forests of Andhra Pradesh, Tamil Nadu, and Karnataka. However, it is not found in tropical rainforests. It is a protected species under the Convention on International Trade in Endangered Species (CITES).

Q37. With reference to ‘dugong’, a mammal found in India, which of the following statements is/are correct? (UPSC CSE Pre. 2015)

1. It is a herbivorous marine animal.
2. It is found along the entire coast of India.
3. It is given legal protection under Schedule I of the Wildlife (Protection) Act, 1972.

Select the correct answer using the codes given below.
 (a) 1 and 2 only
 (b) 2 only
 (c) 1 and 3 only
 (d) 3 only

Solution: (c)

Explanation:
 Dugongs are herbivorous marine mammals found in India’s Gulf of Mannar, Palk Bay, Gulf of Kutch, and Andaman and Nicobar Islands. They are not found along the entire Indian coastline. They are protected under Schedule I of the Wildlife (Protection) Act, 1972, and are listed as ‘Vulnerable’ on the IUCN Red List.

Q38. Which one of the following is the national aquatic animal of India? (UPSC CSE Pre. 2015)

(a) Saltwater crocodile
 (b) Olive ridley turtle
 (c) Gangetic dolphin
 (d) Gharial

Solution: (c)

Explanation:
 The Gangetic river dolphin is the National Aquatic Animal of India. It is classified as ‘Endangered’ and is protected under Schedule I of the Wildlife (Protection) Act, 1972. Habitat degradation, poaching, and construction of barrages have contributed to its declining population.

Q39. Which one of the following regions of India has a combination of mangrove forest, evergreen forest, and deciduous forest? (UPSC CSE Pre. 2015)

(a) Coastal Andhra Pradesh
 (b) South-West Bengal
 (c) Southern Saurashtra
 (d) Andaman and Nicobar Islands

Solution: (d)

Explanation:
 The Andaman and Nicobar Islands have a unique blend of vegetation, including mangrove forests, evergreen forests, and deciduous forests. They also have submontane hill valley swamp forests, making their biodiversity one of the richest in India.

Q40. Other than poaching, what are the possible reasons for the decline in the population of Ganges River Dolphins? (UPSC CSE Pre. 2014)

1. Construction of dams and barrages on rivers
2. Increase in the population of crocodiles in rivers
3. Getting trapped in fishing nets accidentally
4. Use of synthetic fertilizers and other agricultural chemicals in crop fields in the vicinity of rivers

Select the correct answer using the code given below.
 (a) 1 and 2 only
 (b) 2 and 3 only
 (c) 1, 3 and 4 only
 (d) 1, 2, 3 and 4

Solution: (c)

Explanation:
 The Ganges river dolphin population has been declining due to habitat destruction caused by dams and barrages, accidental entanglement in fishing nets, and pollution from agricultural chemicals. The increase in crocodile populations has not been a significant factor affecting dolphin numbers.

Q41. If you walk through the countryside, you are likely to see some birds stalking alongside cattle to seize the insects disturbed by their movement through grasses. Which one of the following is/are such bird(s)? (UPSC CSE Pre. 2014)

1. Painted Stork
2. Common Myna
3. Black-necked Crane

Select the correct answer using the code given below.
 (a) 1 and 2 only
 (b) 2 only
 (c) 2 and 3 only
 (d) 3 only

Solution: (b)

Explanation:
 The Common Myna is an omnivorous bird often found near cattle, feeding on insects disturbed by their movement. Painted Storks are wading birds that mainly eat fish, while the Black-necked Crane is found in high-altitude wetlands of the Trans-Himalayas, not in countryside areas.

Q42. Consider the following fauna of India: (UPSC CSE Pre. 2014)

1. Gharial
2. Leatherback turtle
3. Swamp deer

Which of the above is/are endangered?
 (a) 1 and 2 only
 (b) 3 only
 (c) 1, 2 and 3
 (d) None

Solution: (c)

Explanation:
 The Gharial, Leatherback Turtle, and Swamp Deer are all classified as endangered species in India. The Gharial is primarily found in the Chambal River, the Leatherback Turtle is seen along the Indian coastline, and the Swamp Deer is found in swampy grasslands of northern and central India.

Q43. Consider the following: (UPSC CSE Pre. 2013)

1. Star tortoise
2. Monitor lizard
3. Pygmy hog
4. Spider monkey

Which of the above are naturally found in India?
 (a) 1, 2 and 3 only
 (b) 2 and 3 only
 (c) 1 and 4 only
 (d) 1, 2, 3 and 4

Solution: (a)

Explanation:
 The Indian star tortoise, monitor lizard, and pygmy hog are all naturally found in India. The Indian star tortoise inhabits dry forests and scrublands, monitor lizards are widely distributed across India, and the pygmy hog is an endangered species found in Assam. However, spider monkeys are native to Central and South America and are not found in India.

Q44. Consider the following animals: (UPSC CSE Pre. 2013)

1. Sea cow
2. Sea horse
3. Sea lion

Which of the above is/are mammal(s)?
 (a) 1 only
 (b) 1 and 3 only
 (c) 2 and 3 only
 (d) 1, 2 and 3

Solution: (b)

Explanation:
 Sea cows (dugongs) and sea lions are marine mammals that give birth to live young and nurse them with milk. In contrast, the sea horse is a type of fish, not a mammal.

Q45. In which of the following states is the lion-tailed macaque found in its natural habitat? (UPSC CSE Pre. 2013)

1. Tamil Nadu
2. Kerala
3. Karnataka
4. Andhra Pradesh

Select the correct answer using the codes given below:
 (a) 1, 2 and 3 only
 (b) 2 only
 (c) 1, 3 and 4 only
 (d) 1, 2, 3 and 4

Solution: (a)

Explanation:
 The lion-tailed macaque is endemic to the Western Ghats and is primarily found in the evergreen forests of Tamil Nadu, Kerala, and Karnataka. It is not naturally found in Andhra Pradesh. This species is listed as ‘Endangered’ due to habitat destruction and fragmentation.

CLIMATE CHANGE

Q1. In the making of how many of the following are hydrofluorocarbons (HFCs) used? (UPSC CSE Pre 2023)

1. Aerosols
2. Foam agents
3. Fire retardants
4. Lubricants

(a) Only one
 (b) Only two
 (c) Only three
 (d) All four

Solution: (d)

Explanation:
 Hydrofluorocarbons (HFCs) are man-made compounds used in various industrial applications.

• Aerosols: HFCs serve as propellants in spray products.
• Foam Agents: HFCs act as blowing agents in the production of insulating foams.
• Fire Retardants: Some HFCs are used in fire suppression systems.
• Lubricants: HFC-based hydraulic fluids (water-glycol type) are used in various industrial applications.

Thus, all four applications involve HFCs.

Q2. Consider the following statements regarding carbon markets: (UPSC CSE Pre 2023)

• Statement-I: Carbon markets are likely to be one of the most widespread tools in the fight against climate change.
• Statement-II: Carbon markets transfer resources from the private sector to the State.

Which one of the following is correct?
 (a) Both Statement-I and Statement-II are correct, and Statement-II is the correct explanation of Statement-I.
 (b) Both Statement-I and Statement-II are correct, but Statement-II is not the correct explanation of Statement-I.
 (c) Statement-I is correct, but Statement-II is incorrect.
 (d) Statement-I is incorrect, but Statement-II is correct.

Solution: (a)

Explanation:

• Statement I is correct: Carbon markets create a system where entities trade emission allowances, making them an important tool for reducing greenhouse gases.
• Statement II is correct: Carbon markets involve financial transactions that can shift funds from private entities (companies) to the State in the form of taxes, fees, or allowances.
• Statement II correctly explains Statement I, as the transfer of financial resources through carbon pricing mechanisms is an essential part of how carbon markets function.

Q3. How many of the following activities are often considered for carbon capture and sequestration? (UPSC CSE Pre 2023)

1. Spreading finely ground basalt rock on farmlands extensively
2. Increasing the alkalinity of oceans by adding lime
3. Capturing carbon dioxide released by industries and injecting it into abandoned subterranean mines

(a) Only one
 (b) Only two
 (c) All three
 (d) None

Solution: (c)

Explanation:

• Spreading finely ground basalt rock on farmlands (Enhanced Weathering) accelerates natural CO₂ capture through chemical reactions.
• Increasing ocean alkalinity by adding lime enhances the ocean’s ability to absorb and store CO₂.
• Carbon capture and storage (CCS) involves capturing CO₂ emissions from industrial sources and storing them in underground reservoirs.

Since all three methods are commonly discussed for carbon sequestration, the correct answer is (c) All three.

Q4. With reference to green hydrogen, how many of the following statements are correct? (UPSC CSE Pre 2023)

1. It can be used directly as a fuel for internal combustion.
2. It can be blended with natural gas for heat or power generation.
3. It can be used in hydrogen fuel cells to power vehicles.

(a) Only one
 (b) Only two
 (c) All three
 (d) None

Solution: (c)

Explanation:

• Statement 1 is correct: Hydrogen can be used in internal combustion engines, similar to gasoline or diesel.
• Statement 2 is correct: Green hydrogen can be mixed with natural gas for cleaner energy production.
• Statement 3 is correct: Hydrogen fuel cells convert hydrogen into electricity, which powers electric vehicles.

Thus, all three statements are correct.

Q5. Which lake in West Africa has dried up and turned into a desert? (UPSC CSE Pre 2022)

(a) Lake Victoria
 (b) Lake Faguibine
 (c) Lake Oguta
 (d) Lake Volta

Solution: (b)

Explanation:
 Lake Faguibine in Mali has dried up due to prolonged droughts, particularly since the 1970s. Once a major freshwater lake, it has largely turned into dry land, affecting agriculture and livelihoods in the region.

Q6. Consider the following statements about clouds: (UPSC CSE Pre 2022)

1. High clouds primarily reflect solar radiation and cool the Earth’s surface.
2. Low clouds absorb infrared radiation from the Earth’s surface and cause a warming effect.

Which of the statements is/are correct?

(a) 1 only
 (b) 2 only
 (c) Both 1 and 2
 (d) Neither 1 nor 2

Solution: (d)

Explanation:

• Statement 1 is incorrect: High, thin clouds allow solar radiation to pass through but trap infrared radiation, leading to a warming effect rather than cooling.
• Statement 2 is incorrect: Low, thick clouds primarily reflect solar radiation, leading to cooling rather than warming.

Thus, neither statement is correct.

Q7. What is blue carbon? (UPSC CSE Pre. 2021)
(a) Carbon captured by oceans and coastal ecosystems
 (b) Carbon sequestered in forest biomass and agricultural soils
 (c) Carbon contained in petroleum and natural gas
 (d) Carbon present in the atmosphere

Solution: (a)
 Explanation: "Blue carbon" refers to the carbon stored in coastal and marine ecosystems such as mangroves, tidal marshes, and seagrass meadows. These ecosystems sequester and store large amounts of carbon dioxide, helping mitigate climate change.

Q8.Which one of the following statements best describes the term 'Social Cost of Carbon'? (UPSC CSE Pre. 2020)
It is a measure, in monetary value, of the:
 (a) long-term damage done by a tonne of CO₂ emissions in a given year.
 (b) requirement of fossil fuels for a country to provide goods and services to its citizens.
 (c) efforts put in by a climate refugee to adapt to living in a new place.
 (d) contribution of an individual person to the carbon footprint on Earth.

Solution: (a)
 Explanation: The Social Cost of Carbon (SCC) is the economic cost of emitting an additional ton of CO₂ into the atmosphere, considering its impact on climate change, human health, and economic activity over a long period.

Q9. In the context of which of the following do some scientists suggest the use of cirrus cloud thinning technique and the injection of sulphate aerosol into the stratosphere? (UPSC CSE Pre. 2019)
(a) Creating artificial rains in some regions
 (b) Reducing the frequency and intensity of tropical cyclones
 (c) Reducing the adverse effects of solar wind on Earth
 (d) Reducing global warming

Solution: (d)
 Explanation: Cirrus cloud thinning reduces their ability to trap heat, and stratospheric aerosol injection involves releasing reflective sulfate particles to reflect sunlight and cool the planet, both methods aiming to counteract global warming.

Q10. Which of the following statements best describes "carbon fertilization"? (UPSC CSE Pre. 2018)
(a) Increased plant growth due to increased CO₂ concentration in the atmosphere
 (b) Increased temperature of Earth due to increased CO₂ concentration in the atmosphere
 (c) Increased acidity of oceans as a result of increased CO₂ concentration in the atmosphere
 (d) Adaptation of all living beings to climate change caused by increased CO₂ levels

Solution: (a)
 Explanation: Carbon fertilization refers to the enhanced growth of plants due to higher CO₂ levels, which boosts photosynthesis and increases crop yields, though it may have mixed effects on plant nutrition and water usage.

Q11. In the context of mitigating global warming, which of the following can be potential sites for carbon sequestration? (UPSC CSE Pre. 2017)

1. Abandoned and uneconomic coal seams
2. Depleted oil and gas reservoirs
3. Subterranean deep saline formations

Select the correct answer using the code below:
 (a) 1 and 2 only
 (b) 3 only
 (c) 1 and 3 only
 (d) 1, 2, and 3

Solution: (d)
 Explanation: Carbon sequestration involves storing CO₂ in geological formations to reduce its atmospheric presence. Abandoned coal seams, depleted oil and gas reservoirs, and deep saline formations are all viable sites for underground carbon storage.

Q12.What is the Rio+20 Conference, often mentioned in the news? (UPSC CSE Pre. 2015)
(a) The United Nations Conference on Sustainable Development
 (b) A Ministerial Meeting of the World Trade Organization
 (c) A Conference of the Intergovernmental Panel on Climate Change
 (d) A Conference of the Member Countries of the Convention on Biological Diversity

Solution: (a)
 Explanation: The United Nations Conference on Sustainable Development, also known as Rio+20, took place in Rio de Janeiro, Brazil, in June 2012. It led to global commitments for sustainable development and the launch of the Sustainable Development Goals (SDGs).

Q13. Which one of the following is associated with the issue of control and phasing out of the use of ozone-depleting substances? (UPSC CSE Pre. 2015)
(a) Bretton Woods Conference
 (b) Montreal Protocol
 (c) Kyoto Protocol
 (d) Nagoya Protocol

Solution: (b)
 Explanation: The Montreal Protocol (1987) is an international treaty designed to phase out substances that deplete the ozone layer. It has been ratified by all 198 UN member states and has significantly helped in restoring the ozone layer.

Q14. The scientific view is that the increase in global temperature should not exceed 2°C above pre-industrial levels. If the global temperature increases beyond 3°C above the pre-industrial level, what can be its possible impact(s) on the world? (UPSC CSE Pre. 2014)

Terrestrial biosphere tends toward a net carbon source.

Widespread coral mortality will occur.

All the global wetlands will permanently disappear.

Cultivation of cereals will not be possible anywhere in the world.

Select the correct answer using the code below:
 (a) 1 only
 (b) 1 and 2 only
 (c) 2, 3 and 4 only
 (d) 1, 2, 3 and 4

Solution: (b)
 Explanation:

• Statement 1 is correct: At temperatures beyond 3°C above pre-industrial levels, the terrestrial biosphere, which currently absorbs CO₂, may release more CO₂ than it absorbs, making it a net carbon source.
• Statement 2 is correct: Coral bleaching and mortality will increase significantly with rising ocean temperatures.
• Statement 3 and 4 are incorrect: While climate change will impact wetlands and agriculture, a complete disappearance of all wetlands and an absolute halt in cereal cultivation are extreme statements. Some regions may still sustain agriculture with adaptation.

Q15. Consider the following statements: Chlorofluorocarbons, known as ozone-depleting substances, are used (UPSC CSE Pre. 2014)

1. In the production of plastic foams.
2. In the production of tubeless tyres.
3. In cleaning certain electronic components.
4. As pressurizing agents in aerosol cans.

Which of the statements given above is/are correct?
 (a) 1, 2 and 3 only
 (b) 4 only
 (c) 1, 3 and 4 only
 (d) 1, 2, 3 and 4

Solution: (c)
 Explanation: Chlorofluorocarbons (CFCs) are synthetic chemicals composed of carbon, chlorine, and fluorine. They have been widely used as aerosol propellants, refrigerants, and solvents. They are also used in the manufacture of plastic foams and in cleaning electronic components. However, CFCs are not used in the production of tubeless tyres.

Q16. The increasing amount of carbon dioxide in the air is slowly raising the temperature of the atmosphere, because it absorbs (UPSC CSE Pre. 2014)
(a) The water vapour of the air and retains its heat.
 (b) The ultraviolet part of the solar radiation.
 (c) All the solar radiations.
 (d) The infrared part of the solar radiation.

Solution: (d)
 Explanation: Carbon dioxide (CO₂) is a greenhouse gas that absorbs infrared radiation emitted by the Earth's surface and re-emits it in all directions, causing a warming effect. This process, known as the greenhouse effect, contributes to global warming. Unlike ozone, CO₂ does not absorb ultraviolet radiation, and it does not absorb all solar radiation, only infrared radiation. Additionally, while water vapor is a greenhouse gas, CO₂ does not absorb water vapor.

NATIONAL AND INTERNATIONAL EFFORTS TO COMBAT CLIMATE CHANGE

Q1. Which one of the following is the correct description of "100 Million Farmers"? [UPSC CSE Pre 2024]

(a) It is a platform for accelerating the transition towards food and water systems that are net-zero (carbon), nature-positive, and that aims to increase farmer resilience.
 (b) It is an international alliance and a network of individuals and farming organizations interested in supporting and strengthening the development of organic animal husbandry.
 (c) It is a digital platform fully integrated with service providers and built on blockchain that lets buyers, sellers, and third parties trade fertilizers quickly and securely.
 (d) It is a platform with the mission of encouraging farmers to form Farmer Producer Organizations or Agribusiness Consortiums, thus facilitating access to global open markets to sell their products.

Explanation:

• "100 Million Farmers" is a global platform that aims to accelerate the transition towards sustainable food and water systems, ensuring they are net-zero in carbon emissions, nature-positive, and focused on improving farmer resilience.
• The initiative supports public and private stakeholders in integrating farmers into the global climate and nature agenda by promoting sustainable agricultural practices.
• It does not specifically focus on organic animal husbandry (option b), blockchain-based fertilizer trading (option c), or solely facilitating farmer access to markets (option d).

Thus, the correct answer is (a). 

Q2. The 'Invasive Species Specialist Group' (that develops the Global Invasive Species Database) belongs to which one of the following organizations? (UPSC CSE Pre. 2023)
(a) The International Union for Conservation of Nature
 (b) The United Nations Environment Programme
 (c) The United Nations World Commission for Environment and Development
 (d) The World Wide Fund for Nature

Solution: (a)
 Exp) The Invasive Species Specialist Group (ISSG) is a global network of scientific and policy experts on invasive species, organized under the auspices of the Special Survival Commission (SSC) of The International Union for Conservation of Nature (IUCN). The ISSG promotes and facilitates the global interchange of knowledge and information on invasive species, ensuring the connection between knowledge, practice, and policy so that decisions are well-informed. Policy and technical guidance, as well as information sharing through its online tools, resources, and networking, are the ISSG's two main focus areas.

Q3."Climate Action Tracker," which monitors the emission reduction pledges of different countries, is a: (UPSC CSE Pre. 2022)
(a) Database created by a coalition of research organizations
 (b) Wing of the "International Panel on Climate Change"
 (c) Committee under the "United Nations Framework Convention on Climate Change"
 (d) Agency promoted and financed by the United Nations Environment Programme and World Bank

Solution: (a)
 Exp) Climate Action Tracker is an independent scientific analysis produced by two research organizations, namely Climate Analytics and New Climate Institute, for tracking climate action since 2009. It monitors 32 countries, accounting for more than 80% of global emissions. The Climate Action Tracker assesses government climate action and measures it against the globally agreed Paris Agreement aim of "holding warming well below 2°C, and pursuing efforts to limit warming to 1.5°C."

Q4. Consider the following statements: (UPSC CSE Pre. 2022)

1. "The Climate Group" is an international non-profit organization that drives climate action by building large networks and running them.
2. The International Energy Agency, in partnership with the Climate Group, launched a global initiative "EP100."
3. EP100 brings together leading companies committed to driving innovation in energy efficiency and increasing competitiveness while delivering on emission reduction goals.
4. Some Indian companies are members of EP100.
5. The International Energy Agency is the Secretariat to the "Under2 Coalition."

Which of the statements given above are correct?
 (a) 1, 2, 4, and 5 only
 (b) 1, 3, and 4 only
 (c) 2, 3, and 5 only
 (d) 1, 2, 3, 4, and 5

Solution: (b)
 Exp)

• Statement 1 is correct: The Climate Group is an international non-profit founded in 2003, with offices in London, New York, New Delhi, Amsterdam, and Beijing. It drives climate action by building a large network. Currently, its network includes over 500 multinational businesses in 175 markets worldwide.
• Statement 2 is incorrect: EP100 is a global initiative led by The Climate Group and the Alliance to Save Energy, not by the International Energy Agency.
• Statement 3 is correct: The Climate Group’s EP100 initiative brings together companies committed to improving energy productivity and reducing greenhouse gas emissions.
• Statement 4 is correct: Indian companies, such as Mahindra Group, are part of EP100 and are working toward energy efficiency.
• Statement 5 is incorrect: The Climate Group, not the International Energy Agency, serves as the Secretariat to the Under2 Coalition.

Q5.Consider the following statements: (UPSC CSE Pre. 2022)

1. The India Sanitation Coalition is a platform to promote sustainable sanitation and is funded by the Government of India and the World Health Organization.
2. The National Institute of Urban Affairs is an apex body of the Ministry of Housing and Urban Affairs in the Government of India and provides innovative solutions to address the challenges of urban India.

Which of the statements given above is/are correct?
 (a) 1 only
 (b) 2 only
 (c) Both 1 and 2
 (d) Neither 1 nor 2

Solution: (d)
 Exp)

• Statement 1 is incorrect: The India Sanitation Coalition (ISC), launched in June 2015 at the Federation of Indian Chambers of Commerce and Industry (FICCI), supports safe and sustainable sanitation by bringing multiple organizations together. It is not funded by WHO.
• Statement 2 is incorrect: The National Institute of Urban Affairs (NIUA) is an autonomous research and training institute established in 1976 under the Societies Registration Act. While it is supported by the Ministry of Housing and Urban Affairs, it is not an apex body under the Ministry.

Q6. Which one of the following has been constituted under the Environment (Protection) Act, 1986? (UPSC CSE Pre. 2022)
(a) Central Water Commission
 (b) Central Ground Water Board
 (c) Central Ground Water Authority
 (d) National Water Development Agency

Solution: (c)
 Exp) The Central Ground Water Authority (CGWA) has been constituted under Section 3(3) of the Environment (Protection) Act, 1986, to regulate and control the development and management of groundwater resources in the country.

Q7. With reference to Indian laws about wildlife protection, consider the following statements: (UPSC CSE Pre. 2022)

1. Wild animals are the sole property of the government.
2. When a wild animal is declared protected, such an animal is entitled to equal protection whether it is found in protected areas or outside.
3. Apprehension of a protected wild animal becoming a danger to human life is sufficient ground for its capture or killing.

Which of the statements given above is/are correct?
 (a) 1 and 2
 (b) 2 only
 (c) 1 and 3
 (d) 3 only

Solution: (b)
 Exp)

• Statement 1 is incorrect: As per the official answer key, this statement is incorrect. Although different state and central government websites provide varying information, stating that wild animals are the "sole property" of the government is an extreme statement and is therefore incorrect.
• Statement 2 is correct: The Wildlife (Protection) Act, 1972, does not discriminate between animals found in protected areas and those outside. It provides equal protection for wild animals, irrespective of their location.
• Statement 3 is incorrect: According to the Wildlife (Protection) Act, 1972, only if a wild animal becomes a danger to human life or is diseased or disabled beyond recovery can it be captured or killed. This decision must be made by the competent authority, the Chief Wildlife Warden of the State. Mere apprehension or fear that a wild animal could endanger human life is not a valid ground for capture or killing.

Q8. With reference to the 'New York Declaration on Forests', which of the following statements are correct? (UPSC CSE Pre. 2021)

1. It was first endorsed at the United Nations Climate Summit in 2014.
2. It endorses a global timeline to end the loss of forests.
3. It is a legally binding international declaration.
4. It is endorsed by governments, big companies, and indigenous communities.
5. India was one of the signatories at its inception.

Select the correct answer using the code given below:
 (a) 1, 2, and 4
 (b) 1, 3, and 5
 (c) 3 and 4
 (d) 2 and 5

Solution: (a)
 Exp)

• Statement 1 is correct: The New York Declaration on Forests (NYDF) was first endorsed at the United Nations Climate Summit in September 2014.
• Statement 2 is correct: NYDF sets a target to halt natural forest loss by 2030.
• Statement 3 is incorrect: NYDF is a voluntary and non-binding declaration.
• Statement 4 is correct: NYDF has over 200 endorsers, including national governments, subnational governments, companies, indigenous groups, financial institutions, and NGOs.
• Statement 5 is incorrect: India has not signed the NYDF.

Q9. The 'Common Carbon Metric', supported by UNEP, has been developed for: (UPSC CSE Pre. 2021)

(a) Assessing the carbon footprint of building operations around the world
 (b) Enabling commercial farming entities to enter carbon emission trading
 (c) Enabling governments to assess the overall carbon footprint of their countries
 (d) Assessing the overall carbon footprint caused by fossil fuel use globally

Solution: (a)
 Exp) The Common Carbon Metric is a protocol developed by UNEP’s Sustainable Buildings & Climate Initiative (UNEP-SBCI) to measure energy use and report greenhouse gas (GHG) emissions from building operations. It helps track progress in reducing emissions through improved energy efficiency in buildings.

Q10. In the context of India's preparation for climate-smart agriculture, consider the following statements: (UPSC CSE Pre. 2021)

1. The 'Climate-Smart Village' approach in India is a part of a project led by the Climate Change, Agriculture and Food Security (CCAFS) program.
2. The CCAFS project is carried out under the Consultative Group on International Agricultural Research (CGIAR), headquartered in France.
3. The International Crops Research Institute for the Semi-Arid Tropics (ICRISAT) in India is one of CGIAR's research centers.

Which of the statements given above are correct?
 (a) 1 and 2 only
 (b) 2 and 3 only
 (c) 1 and 3 only
 (d) 1, 2, and 3

Solution: (d)
 Exp)

• Statement 1 is correct: The Climate-Smart Village approach in India is part of CGIAR’s Research Program on Climate Change, Agriculture, and Food Security (CCAFS).
• Statement 2 is correct: CCAFS is part of CGIAR, headquartered in Montpellier, France.
• Statement 3 is correct: ICRISAT is a CGIAR research center working in India and other regions.

Q11. Consider the following statements: (UPSC CSE Pre. 2021)

Statement 1: The United Nations Capital Development Fund (UNCDF) and the Arbor Day Foundation have recently recognized Hyderabad as the 2020 Tree City of the World.
 Statement 2: Hyderabad was selected for this recognition due to its commitment to growing and maintaining urban forests.

Which one of the following is correct?
 (a) Both statements 1 and 2 are correct, and statement 2 is the correct explanation of statement 1
 (b) Both statements 1 and 2 are correct, but statement 2 is not the correct explanation of statement 1
 (c) Statement 1 is correct, but statement 2 is incorrect
 (d) Statement 1 is incorrect, but statement 2 is correct

Solution: (d)
 Exp)

• Statement 1 is incorrect: Hyderabad was recognized as a 2020 Tree City of the World by the Arbor Day Foundation and the Food and Agriculture Organization (FAO), not by the UNCDF.
• Statement 2 is correct: The recognition was based on Hyderabad’s efforts to maintain and grow urban forests.

Q12. Consider the following statements: (UPSC CSE Pre. 2020)

1. 36% of India's districts are classified as "overexploited" or "critical" by the Central Ground Water Authority (CGWA).
2. CGWA was formed under the Environment (Protection) Act.
3. India has the largest area under groundwater irrigation in the world.

Which of the statements given above is/are correct?
 (a) 1 only
 (b) 2 and 3 only
 (c) 2 only
 (d) 1 and 3 only

Solution: (b)
 Exp)

• Statement 1 is incorrect: About 22% of India’s groundwater assessment units are categorized as overexploited or critical, not 36%.
• Statement 2 is correct: CGWA was formed under Section 3(3) of the Environment (Protection) Act, 1986.
• Statement 3 is correct: India has the largest area under groundwater irrigation, covering about 39 million hectares (67% of total irrigation).

Q13. Among the following Tiger Reserves, which one has the largest area under "Critical Tiger Habitat"? (UPSC CSE Pre. 2020)

(a) Corbett
 (b) Ranthambore
 (c) Nagarjunsagar-Srisailam
 (d) Sunderbans

Solution: (c)
 Exp)
 The Critical Tiger Habitat (CTH) areas in the given reserves are:

• Nagarjunsagar-Srisailam: 2595 sq. km.
• Sunderbans: 1699.62 sq. km.
• Ranthambore: 1113.36 sq. km.
• Corbett: 821.99 sq. km.
  Thus, Nagarjunsagar-Srisailam has the largest area under CTH.

Q14. Which one of the following protected areas is well known for the conservation of a subspecies of the Indian swamp deer (Barasingha) that thrives well on hard ground and is exclusively graminivorous? (UPSC CSE Pre. 2020)

(a) Kanha National Park
 (b) Manas National Park
 (c) Mudumalai Wildlife Sanctuary
 (d) Tal Chhapar Wildlife Sanctuary

Solution: (a)
 Exp) Kanha Tiger Reserve is the only place in the wild where the Hard-ground Barasingha (Cervus duvaucelii branderi) is found. This subspecies is exclusively graminivorous (grass-eating) and is distinct from the swamp-dwelling Barasingha found in other parts of India.

Q15. Likely Habitats of Musk Deer
Which of the following locations are most suitable for finding the musk deer in its natural habitat?

14. Askot Wildlife Sanctuary
15. Gangotri National Park
16. Kishanpur Wildlife Sanctuary
17. Manas National Park

Select the correct answer using the code given below:
 (a) 1 and 2 only
 (b) 2 and 3 only
 (c) 3 and 4 only
 (d) 1 and 4 only

Answer: (a)

Explanation:
 Musk deer predominantly inhabit forested and alpine scrub regions across the Himalayan landscape.

• Askot Wildlife Sanctuary, situated in Pithoragarh, Uttarakhand, is specifically designated for the conservation of musk deer.
• Gangotri National Park also provides a suitable environment for this species.
• However, Kishanpur Wildlife Sanctuary and Manas National Park do not align with the preferred high-altitude habitats of the musk deer.

Q16. Implications of Listing a Plant in Schedule VI of the Wildlife Protection Act, 1972
If a plant species is classified under Schedule VI of the Wildlife Protection Act, 1972, what does it signify?

(a) A license is required for its cultivation.
 (b) Its cultivation is strictly prohibited under all circumstances.
 (c) It refers to a genetically modified (GM) crop.
 (d) It is classified as an invasive species harmful to the ecosystem.

Answer: (a)

Explanation:

• The Wildlife Protection Act, 1972, covers the protection of animals and plants, with Schedule VI specifically regulating plant species.
• Any species listed in Schedule VI cannot be cultivated, possessed, or traded without prior authorization from the relevant authorities.
• The law aims to prevent exploitation and ensure the conservation of rare and endangered plant species.

Q17. Raw Materials for Biofuels under India's National Policy on Biofuels
Which of the following can be used as raw materials for biofuel production according to India’s National Policy on Biofuels?

16. Cassava
17. Damaged wheat grains
18. Groundnut seeds
19. Horse grams
20. Rotten potatoes
21. Sugar beet

Select the correct answer using the code below:
 (a) 1, 2, 5, and 6 only
 (b) 1, 3, 4, and 6 only
 (c) 2, 3, 4, and 5 only
 (d) 1, 2, 3, 4, 5, and 6

Answer: (a)

Explanation:
 The National Policy on Biofuels allows the use of various agricultural residues and non-edible crops for biofuel production.

• Approved raw materials include cassava, sugar beet, damaged wheat grains, and rotten potatoes as they can be processed into bioethanol.
• However, groundnut seeds and horse grams are primarily food crops and are not preferred for biofuel production.

Q18. Compensatory Afforestation Fund Act, 2016
Consider the following statements regarding the Compensatory Afforestation Fund Act, 2016:

1. The Compensatory Afforestation Fund Management and Planning Authority (CAMPA) functions at both the national and state levels.
2. The Act mandates people’s participation in compensatory afforestation programs.

Which of the statements given above is/are correct?

(a) 1 only
 (b) 2 only
 (c) Both 1 and 2
 (d) Neither 1 nor 2

Answer: (a)

Explanation:

• The Act establishes National and State CAMPA bodies to manage funds for afforestation and forest restoration.
• However, there is no explicit requirement in the Act mandating people’s participation in afforestation programs.

Q19. Agasthyamalai Biosphere Reserve
Which of the following protected areas are part of the Agasthyamalai Biosphere Reserve?

(a) Neyyar, Peppara, and Shendurney Wildlife Sanctuaries; and Kalakad Mundanthurai Tiger Reserve
 (b) Mudumalai, Sathyamangalam, and Wayanad Wildlife Sanctuaries; and Silent Valley National Park
 (c) Kaundinya, Gundla Brahmeswaram, and Papikonda Wildlife Sanctuaries; and Mukurthi National Park
 (d) Kawal and Sri Venkateswara Wildlife Sanctuaries; and Nagarjunasagar-Srisailam Tiger Reserve

Answer: (a)

Explanation:

• The Agasthyamalai Biosphere Reserve, located in the Western Ghats, comprises Neyyar, Peppara, and Shendurney Wildlife Sanctuaries, along with the Kalakad Mundanthurai Tiger Reserve.
• This reserve is a recognized UNESCO Biosphere Reserve and a significant biodiversity hotspot.

Q20. National Park in the Temperate Alpine Zone
Which of the following national parks is entirely situated in the temperate alpine region?

(a) Manas National Park
 (b) Namdapha National Park
 (c) Neora Valley National Park
 (d) Valley of Flowers National Park

Answer: (d)

Explanation:

• Valley of Flowers National Park in Uttarakhand is a high-altitude temperate alpine ecosystem, known for its unique floral diversity.
• Other options, such as Manas, Namdapha, and Neora Valley National Parks, have tropical and subtropical characteristics.

Q21. Wetlands Conservation in India
Consider the following statements:

1. Under the Ramsar Convention, the Government of India is legally required to protect and conserve all wetlands within its territory.
2. The Wetlands (Conservation and Management) Rules, 2010, were formulated based on recommendations from the Ramsar Convention.
3. These rules include the drainage area or catchment region of the wetlands within their regulatory framework.

Which of the statements given above is/are correct?

(a) 1 and 2 only
 (b) 2 and 3 only
 (c) 3 only
 (d) 1, 2, and 3

Answer: (c)

Explanation:

• The Ramsar Convention does not impose a mandatory legal obligation on India to protect all wetlands, only designated Ramsar sites.
• The Wetlands (Conservation and Management) Rules, 2010, were developed independently by the Indian government and not directly based on the Ramsar Convention.
• However, these rules do extend to the catchment areas affecting wetlands.

Q22. Differences Between NGT and CPCB
How does the National Green Tribunal (NGT) differ from the Central Pollution Control Board (CPCB)?

The NGT was established by an Act of Parliament, whereas the CPCB was created by an executive order of the government.

The NGT delivers environmental justice and reduces litigation burdens on higher courts, while the CPCB primarily monitors water and air pollution levels.

Which of the statements given above is/are correct?

(a) 1 only
 (b) 2 only
 (c) Both 1 and 2
 (d) Neither 1 nor 2

Answer: (b)

Explanation:

• Statement 1 is incorrect: The CPCB was created under the Water (Prevention and Control of Pollution) Act, 1974, making it a statutory body rather than one created through an executive order.
• Statement 2 is correct: The NGT, established under the NGT Act, 2010, focuses on environmental litigation and dispute resolution, while the CPCB is responsible for pollution monitoring and control.

Q23. In which one of the following States is Pakhui Wildlife Sanctuary located? (UPSC CSE Prelims 2018)

(a) Arunachal Pradesh
 (b) Manipur
 (c) Meghalaya
 (d) Nagaland

Answer: (a)

Explanation:
 Pakhui Wildlife Sanctuary, also known as Pakke Wildlife Sanctuary, is located in the East Kameng district of Arunachal Pradesh. It lies in the foothills of the Eastern Himalayas and is home to a rich diversity of flora and fauna, including tigers, clouded leopards, and hornbills. In 2002, it was designated as a Tiger Reserve under Project Tiger. It is bordered by the Kameng River on the west and the Pakke River on the east, making it an ecologically significant area.

Q24. With reference to the 'Global Alliance for Climate-Smart Agriculture (GACSA),' which of the following statements is/are correct? (UPSC CSE Prelims 2018)

1. GACSA is an outcome of the Climate Summit held in Paris in 2015.
2. Membership of GACSA does not create any binding obligations.
3. India was instrumental in the creation of GACSA.

(a) 1 and 3 only
(b) 2 only
(c) 2 and 3 only
(d) 1, 2, and 3

Answer: (b)

Explanation:

• Statement 1 is incorrect: The Global Alliance for Climate-Smart Agriculture (GACSA) was launched in 2014 during the UN Climate Summit in New York, not in the 2015 Paris Climate Summit.
• Statement 2 is correct: GACSA is a voluntary, multi-stakeholder platform that promotes Climate-Smart Agriculture (CSA) without imposing binding commitments on its members.
• Statement 3 is incorrect: India was not instrumental in the formation of GACSA. However, some Indian NGOs and institutions are associated with it.

Thus, the correct answer is (b) 2 only.

Q25. The Partnership for Action on Green Economy (PAGE), a UN mechanism to assist countries in transitioning towards greener and more inclusive economies, emerged at: (UPSC CSE Prelims 2018)

(a) The Earth Summit on Sustainable Development 2002, Johannesburg
 (b) The United Nations Conference on Sustainable Development 2012, Rio de Janeiro
 (c) The United Nations Framework Convention on Climate Change 2015, Paris
 (d) The World Sustainable Development Summit 2016, New Delhi

Answer: (b)

Explanation:
 The Partnership for Action on Green Economy (PAGE) was launched in 2013 as a response to the United Nations Conference on Sustainable Development (Rio+20) held in 2012. The initiative supports countries in transitioning to sustainable economic models and integrates green economy principles into national policies. PAGE is a collaborative effort of five UN agencies—UNEP, UNDP, ILO, UNIDO, and UNITAR.

Q26. "Momentum for Change: Climate Neutral Now" is an initiative launched by: (UPSC CSE Prelims 2018)

(a) The Intergovernmental Panel on Climate Change (IPCC)
 (b) The UNEP Secretariat
 (c) The UNFCCC Secretariat
 (d) The World Meteorological Organization (WMO)

Answer: (c)

Explanation:
 The "Momentum for Change: Climate Neutral Now" initiative was launched in 2015 by the United Nations Framework Convention on Climate Change (UNFCCC) Secretariat. It aims to promote climate neutrality through three steps:

1. Measuring the carbon footprint,
2. Reducing greenhouse gas emissions, and
3. Offsetting the remaining emissions with UN-certified reductions.

This initiative encourages voluntary participation from individuals, companies, and governments.

Q27. Consider the following statements: (UPSC CSE Prelims 2018)

1. The definition of "Critical Wildlife Habitat" is incorporated in the Forest Rights Act, 2006.
2. For the first time in India, Baigas have been given Habitat Rights.
3. The Union Ministry of Environment, Forest and Climate Change officially decides and declares Habitat Rights for Primitive and Vulnerable Tribal Groups in any part of India.

Which of the statements given above is/are correct?
 (a) 1 and 2 only
 (b) 2 and 3 only
 (c) 3 only
 (d) 1, 2, and 3

Answer: (a)

Explanation:

• Statement 1 is correct: The term "Critical Wildlife Habitat (CWH)" is explicitly defined in the Forest Rights Act, 2006. It refers to areas within National Parks and Wildlife Sanctuaries crucial for wildlife conservation.
• Statement 2 is correct: The Baiga tribe, found in Madhya Pradesh and Chhattisgarh, was the first in India to receive Habitat Rights under the Forest Rights Act, 2006.
• Statement 3 is incorrect: The Ministry of Tribal Affairs, not the Ministry of Environment, Forest, and Climate Change, decides on Habitat Rights for Particularly Vulnerable Tribal Groups (PVTGs) in consultation with Gram Sabhas.

Thus, the correct answer is (a) 1 and 2 only.

Q28. Consider the following statements regarding the Climate and Clean Air Coalition (CCAC): (UPSC CSE Prelims 2017)

1. The CCAC is a unique initiative of the G20 group of countries.
2. The CCAC focuses on methane, black carbon, and hydrofluorocarbons (HFCs).

Which of the statements given above is/are correct?
 (a) 1 only
 (b) 2 only
 (c) Both 1 and 2
 (d) Neither 1 nor 2

Answer: (b)

Explanation:

• Statement 1 is incorrect: The Climate and Clean Air Coalition (CCAC) was launched in 2012 by UNEP and six founding countries—Bangladesh, Canada, Ghana, Mexico, Sweden, and the United States. It is not a G20
• Statement 2 is correct: The CCAC focuses on reducing Short-Lived Climate Pollutants (SLCPs) like methane, black carbon, and hydrofluorocarbons (HFCs), which contribute significantly to global warming.

Thus, the correct answer is (b) 2 only.

Q29. With reference to the 'Global Climate Change Alliance (GCCA),' which of the following statements is/are correct? (UPSC CSE Prelims 2017)

1. It is an initiative of the European Union.
2. It provides technical and financial support to targeted developing countries to integrate climate change into their development policies and budgets.
3. It is coordinated by the World Resources Institute (WRI) and the World Business Council for Sustainable Development (WBCSD).

Which of the statements given above is/are correct?
 (a) 1 and 2 only
 (b) 3 only
 (c) 2 and 3 only
 (d) 1, 2, and 3

Answer: (a)

Explanation:

• Statement 1 is correct: The Global Climate Change Alliance (GCCA) is an initiative of the European Union (EU) launched in 2007.
• Statement 2 is correct: The GCCA provides financial and technical support to Least Developed Countries (LDCs) and Small Island Developing States (SIDS) to integrate climate change measures into national policies.
• Statement 3 is incorrect: The GCCA is coordinated by the European Commission (EC), not by the World Resources Institute (WRI) or the World Business Council for Sustainable Development (WBCSD).

Thus, the correct answer is (a) 1 and 2 only.

Q30. In India, if a species of tortoise is declared protected under Schedule I of the Wildlife (Protection) Act, 1972, what does it imply? (UPSC CSE Prelims 2017)

(a) It enjoys the same level of protection as the tiger.
 (b) It no longer exists in the wild, a few individuals are under captive protection, and now it is impossible to prevent its extinction.
 (c) It is endemic to a particular region of India.
 (d) Both (b) and (c) stated above are correct in this context.

Answer: (a)

Explanation:
 Under the Wildlife (Protection) Act, 1972, species listed under Schedule I receive the highest level of legal protection, similar to tigers and elephants. Hunting or poaching these species is a criminal offense with strict penalties, including fines and imprisonment. This schedule covers highly endangered species requiring utmost conservation efforts.

Q31. According to the Wildlife (Protection) Act, 1972, which of the following animals cannot be hunted by any person except under some provisions provided by law? (UPSC CSE Prelims 2017)

1. Gharial
2. Indian wild ass
3. Wild buffalo

(a) 1 only
(b) 2 and 3 only
(c) 1 and 3 only
(d) 1, 2, and 3

Answer: (d)

Explanation:
 All three species—Gharial, Indian Wild Ass, and Wild Buffalo—are listed under Schedule I of the Wildlife (Protection) Act, 1972. This means they are given absolute protection, and hunting or harming them is strictly prohibited except in exceptional circumstances permitted by law, such as for scientific research or tribal rights under special provisions.

Q32. With reference to the Agreement at the UNFCCC Meeting in Paris in 2015, which of the following statements is/are correct? (UPSC CSE Prelims 2016)

1. The Agreement was signed by all the member countries of the UN, and it will go into effect in 2017.
2. The Agreement aims to limit greenhouse gas emissions so that the rise in average global temperature by the end of this century does not exceed 2°C or even 1.5°C above pre-industrial levels.
3. Developed countries acknowledged their historical responsibility in global warming and committed to donate $1000 billion a year from 2020 to help developing countries cope with climate change.

(a) 1 and 3 only
(b) 2 only
(c) 2 and 3 only
(d) 1, 2, and 3

Answer: (b)

Explanation:

• Statement 1 is incorrect: Not all UN member countries signed the Paris Agreement. The agreement was adopted in 2015, but it officially came into force on November 4, 2016, and was scheduled to take full effect in 2020.
• Statement 2 is correct: The Paris Agreement's primary goal is to limit global warming to well below 2°C, with efforts to keep it under 5°C above pre-industrial levels.
• Statement 3 is incorrect: Developed nations pledged $100 billion per year (not $1000 billion) to help developing countries adapt to climate change and mitigate its effects.

Q33. Consider the following statements: (UPSC CSE Prelims 2016)

1. The Sustainable Development Goals were first proposed in 1972 by a global think tank called the 'Club of Rome'.
2. The Sustainable Development Goals have to be achieved by 2030.

(a) 1 only
 (b) 2 only
 (c) Both 1 and 2
 (d) Neither 1 nor 2

Answer: (b)

Explanation:

• Statement 1 is incorrect: The Sustainable Development Goals (SDGs) were not proposed in 1972. They were adopted in 2015 at the United Nations Sustainable Development Summit as a successor to the Millennium Development Goals (MDGs).
• Statement 2 is correct: The 17 SDGs are targeted to be achieved by 2030. These goals cover a wide range of issues, including poverty eradication, environmental sustainability, and economic growth.

Q34. The term 'Intended Nationally Determined Contributions' is sometimes seen in the news in the context of: (UPSC CSE Prelims 2016)

(a) Pledges made by European countries to rehabilitate refugees from the war-affected Middle East
 (b) Plan of action outlined by countries to combat climate change
 (c) Capital contributed by member countries in the establishment of the Asian Infrastructure Investment Bank
 (d) Plan of action outlined by countries regarding Sustainable Development Goals

Answer: (b)

Explanation:
 Intended Nationally Determined Contributions (INDCs) refer to voluntary commitments made by countries under the Paris Agreement to reduce greenhouse gas emissions. Each country submits an INDC based on its national priorities, economic capacity, and climate policies. Once a country ratifies the Paris Agreement, its INDC becomes its NDC (Nationally Determined Contribution).

Q35. What is/are the importance of the 'United Nations Convention to Combat Desertification' (UNCCD)? (UPSC CSE Prelims 2016)

1. It aims to promote effective action through innovative national programs and supportive international partnerships.
2. It has a special focus on South Asia and North Africa regions, and its Secretariat facilitates the allocation of the major portion of financial resources to these regions.
3. It is committed to a bottom-up approach, encouraging the participation of local people in combating desertification.

(a) 1 only
 (b) 2 and 3 only
 (c) 1 and 3 only
 (d) 1, 2, and 3

Answer: (c)

Explanation:

• Statement 1 is correct: The UNCCD, adopted in 1994, aims to combat desertification and land degradation through national action plans and international cooperation.
• Statement 2 is incorrect: The UNCCD does not specifically focus on South Asia and North Africa; rather, it addresses desertification worldwide, including regions like Africa, Asia, and Latin America.
• Statement 3 is correct: The convention follows a bottom-up approach, ensuring community participation in combating desertification and promoting sustainable land management.

Q36. The FAO accords the status of 'Globally Important Agricultural Heritage System (GIAHS)' to traditional agricultural systems. What is the overall goal of this initiative? (UPSC CSE Prelims 2016)

1. To provide modern technology, training in modern farming methods, and financial support to local communities of identified GIAHS to greatly enhance their agricultural productivity.
2. To identify and safeguard eco-friendly traditional farm practices and their associated landscapes, agricultural biodiversity, and knowledge systems of the local communities.
3. To provide Geographical Indication (GI) status to all the varieties of agricultural produce in such identified GIAHS.

(a) 1 and 3 only
 (b) 2 only
 (c) 2 and 3 only
 (d) 1, 2, and 3

Answer: (b)

Explanation:

• Statement 1 is incorrect: The Globally Important Agricultural Heritage Systems (GIAHS) program, launched by the Food and Agriculture Organization (FAO) in 2002, does not focus on introducing modern farming methods. Instead, it promotes traditional and sustainable agricultural practices.
• Statement 2 is correct: The primary objective of GIAHS is to preserve traditional agricultural practices, cultural heritage, and biodiversity while ensuring food security.
• Statement 3 is incorrect: GIAHS does not grant Geographical Indication (GI) status to agricultural produce. GI status is a separate recognition under intellectual property rights (IPR)

Q37. Consider the following pairs: (UPSC CSE Prelims 2016)

Terms sometimes seen in the news → Their origin

1. Annex-I Countries → Cartagena Protocol
2. Certified Emissions Reductions → Nagoya Protocol
3. Clean Development Mechanism → Kyoto Protocol

Which of the pairs given above is/are correctly matched?

(a) 1 and 2 only
 (b) 2 and 3 only
 (c) 3 only
 (d) 1, 2, and 3

Answer: (c) 3 only

Explanation:

• Annex-I Countries are part of the Kyoto Protocol, not the Cartagena Protocol. Annex-I consists of industrialized countries that agreed to reduce their greenhouse gas emissions.
• Certified Emissions Reductions (CERs) belong to the Kyoto Protocol’s Clean Development Mechanism (CDM), not the Nagoya Protocol. CERs are carbon credits earned by developing countries for reducing emissions.
• Clean Development Mechanism (CDM) is correctly matched with the Kyoto Protocol. CDM allows developed nations to invest in projects in developing countries to earn carbon credits.

Q38. With reference to an initiative called The Economics of Ecosystems and Biodiversity (TEEB), which of the following statements is/are correct? (UPSC CSE Prelims 2016)

1. It is an initiative hosted by UNEP, IMF, and the World Economic Forum.
2. It is a global initiative that focuses on drawing attention to the economic benefits of biodiversity.
3. It presents an approach that can help decision-makers recognize, demonstrate, and capture the value of ecosystems and biodiversity.

Select the correct answer using the code given below:

(a) 1 and 2 only
 (b) 3 only
 (c) 2 and 3 only
 (d) 1, 2, and 3

Answer: (c) 2 and 3 only

Explanation:

• Statement 1 is incorrect: TEEB is hosted by the United Nations Environment Programme (UNEP), but not by the IMF or the World Economic Forum.
• Statements 2 and 3 are correct: TEEB aims to assess the economic benefits of biodiversity and helps policymakers recognize and integrate biodiversity into economic decision-making. It was initiated by Germany and the European Commission in 2007.

Q39. Proper design and effective implementation of the UN-REDD+ Programme can significantly contribute to: (UPSC CSE Prelims 2016)

1. Protection of biodiversity
2. Resilience of forest ecosystems
3. Poverty reduction

Select the correct answer using the code given below:

(a) 1 and 2 only
 (b) 3 only
 (c) 2 and 3 only
 (d) 1, 2, and 3

Answer: (d) 1, 2, and 3

Explanation:

• The UN-REDD+ Programme is an initiative under the United Nations Framework Convention on Climate Change (UNFCCC) to reduce emissions from deforestation and forest degradation (REDD+).
• It provides financial incentives to developing nations to protect and restore forests, which in turn helps in biodiversity conservation and strengthening forest ecosystems.
• By supporting sustainable forest management, it creates employment opportunities, contributing to poverty reduction.

Q40. What is the Greenhouse Gas Protocol? (UPSC CSE Prelims 2016)

(a) It is an international accounting tool for government and business leaders to understand, quantify, and manage greenhouse gas emissions.
 (b) It is an initiative of the United Nations to offer financial incentives to developing countries to reduce greenhouse gas emissions and adopt eco-friendly technologies.
 (c) It is an intergovernmental agreement ratified by all UN member countries to reduce greenhouse gas emissions to specified levels by the year 2022.
 (d) It is one of the multilateral REDD+ initiatives hosted by the World Bank.

Answer: (a)

Explanation:

• The Greenhouse Gas (GHG) Protocol is a widely used international framework to measure and manage greenhouse gas emissions from businesses, cities, and countries.
• It was developed by the World Resources Institute (WRI) and the World Business Council for Sustainable Development (WBCSD).
• It helps governments, businesses, and organizations to develop climate mitigation strategies and track emissions reductions.

Q41. With reference to Agenda 21, sometimes seen in the news, consider the following statements: (UPSC CSE Prelims 2016)

1. It is a global action plan for sustainable development.
2. It originated in the World Summit on Sustainable Development held in Johannesburg in 2002.

Which of the statements given above is/are correct?

(a) 1 only
 (b) 2 only
 (c) Both 1 and 2
 (d) Neither 1 nor 2

Answer: (a) 1 only

Explanation:

• Statement 1 is correct: Agenda 21 is a non-binding action plan of the United Nations for sustainable development, adopted at the Earth Summit (Rio de Janeiro, 1992).
• Statement 2 is incorrect: Agenda 21 originated in the 1992 Earth Summit, not in the 2002 World Summit on Sustainable Development (Johannesburg).

Q42. In the cities of our country, which among the following atmospheric gases are normally considered in calculating the value of the Air Quality Index (AQI)? (UPSC CSE Prelims 2016)

1. Carbon dioxide
2. Carbon monoxide
3. Nitrogen dioxide
4. Sulfur dioxide
5. Methane

Select the correct answer using the code given below:

(a) 1, 2, and 3 only
 (b) 2, 3, and 4 only
 (c) 1, 4, and 5 only
 (d) 1, 2, 3, 4, and 5

Answer: (b) 2, 3, and 4 only

Explanation:

• In India, the AQI (Air Quality Index) is based on eight pollutants:
  • PM10 (Particulate Matter <10 µm)
  • 5 (Particulate Matter <2.5 µm)
  • Ozone (O3)
  • Nitrogen Dioxide (NO2)
  • Carbon Monoxide (CO)
  • Sulfur Dioxide (SO2)
  • Ammonia (NH3)
  • Lead (Pb)
• Carbon dioxide (CO2) and Methane (CH4) are not included in AQI calculations, hence statements 1 and 5 are incorrect.
• Only Carbon Monoxide (CO), Nitrogen Dioxide (NO2), and Sulfur Dioxide (SO2) are considered in AQI calculations, making option (b) the correct answer.

Q43. Which of the following best describes the aim of the 'Green India Mission' of the Government of India? [UPSC CSE Pre. 2016]

1. Incorporating environmental benefits and costs into the Union and State Budgets, thereby implementing 'green accounting.'
2. Launching the second green revolution to enhance agricultural output to ensure food security for all in the future.
3. Restoring and enhancing forest cover and responding to climate change through a combination of adaptation and mitigation measures.

Select the correct answer using the code given below.
 (a) 1 only
 (b) 2 and 3 only
 (c) 3 only
 (d) 1, 2 and 3

Solution: (c)
 Explanation:
 The National Mission for a Green India (GIM) is one of the eight missions under the National Action Plan on Climate Change (NAPCC). It aims to protect, restore, and enhance India's diminishing forest cover while responding to climate change through adaptation and mitigation measures.

Q44. Which of the following National Parks is unique in being a swamp with floating vegetation that supports rich biodiversity? [UPSC CSE Pre. 2015]

1. Bhitarkanika National Park
2. Keibul Lamjao National Park
3. Keoladeo Ghana National Park
4. Sultanpur National Park

(a) 1
(b) 2
(c) 3
(d) 4

Solution: (b)
 Explanation:
 Keibul Lamjao National Park, located in Manipur, is the only floating national park in the world. It consists of a unique ecosystem with floating vegetation known as phumdis on Loktak Lake, a Ramsar site. It is the last natural habitat of the endangered Sangai deer (Brow-antlered deer).

Q45. Which one of the following National Parks has a climate that varies from tropical to subtropical, temperate, and arctic? [UPSC CSE Pre. 2015]

1. Khangchendzonga National Park
2. Nandadevi National Park
3. Neora Valley National Park
4. Namdapha National Park

(a) 1
(b) 2
(c) 3
(d) 4

Solution: (d)
Explanation:
Namdapha National Park, located in Arunachal Pradesh, is one of India's largest protected areas and a biodiversity hotspot. Due to its vast altitudinal range (200m to over 4500m above sea level), it experiences climatic variations from tropical rainforests to arctic conditions, making it one of the most diverse ecosystems in India.

Q46. Which of the following statements regarding the 'Green Climate Fund' is/are correct? [UPSC CSE Pre. 2015]

1. It is intended to assist developing countries in adaptation and mitigation practices to counter climate change.
2. It is founded under the aegis of UNEP, OECD, Asian Development Bank, and World Bank.

Select the correct answer using the codes given below.
 (a) 1 only
 (b) 2 only
 (c) Both 1 and 2
 (d) Neither 1 nor 2

Solution: (a)
 Explanation:
 The Green Climate Fund (GCF) is a global initiative established under the UNFCCC (United Nations Framework Convention on Climate Change) to support developing countries in their climate action efforts. It aims to finance projects related to mitigation and adaptation. However, it is not founded under the aegis of UNEP, OECD, ADB, or the World Bank—rather, it operates independently with financial oversight from the UNFCCC.

Q47. With reference to an organization known as 'BirdLife International,' which of the following statements is/are correct? [UPSC CSE Pre. 2015]

1. It is a Global Partnership of Conservation Organizations.
2. The concept of 'biodiversity hotspots' originated from this organization.
3. It identifies sites referred to as 'Important Bird and Biodiversity Areas' (IBA).

Select the correct answer using the code given below.
 (a) 1 only
 (b) 2 and 3 only
 (c) 1 and 3 only
 (d) 1, 2 and 3

Solution: (c)
 Explanation:
 BirdLife International is a global partnership of conservation organizations working to conserve birds, their habitats, and biodiversity. The concept of 'biodiversity hotspots' was introduced by Norman Myers in 1988, not by BirdLife International. However, BirdLife International is responsible for identifying and designating Important Bird and Biodiversity Areas (IBA) worldwide.

Q48. The 'BioCarbon Fund Initiative for Sustainable Forest Landscapes' is managed by the: [UPSC CSE Pre. 2015]

1. Asian Development Bank
2. International Monetary Fund
3. United Nations Environment Programme
4. World Bank

(a) 1
 (b) 2
 (c) 3
 (d) 4

Solution: (d)
 Explanation:
 The BioCarbon Fund Initiative for Sustainable Forest Landscapes (ISFL) is a program managed by the World Bank. It promotes sustainable agriculture, forestry, and land-use practices to reduce carbon emissions and enhance carbon sequestration.

Q49. With reference to the 'Forest Carbon Partnership Facility,' which of the following statements is/are correct? [UPSC CSE Pre. 2015]

1. It is a global partnership of governments, businesses, civil society, and Indigenous Peoples.
2. It provides financial aid to universities, individual scientists, and institutions involved in scientific forestry research to develop eco-friendly and climate adaptation technologies.
3. It assists countries in their 'REDD+' (Reducing Emissions from Deforestation and Forest Degradation) efforts by providing them with financial and technical assistance.

Select the correct answer using the code given below.
 (a) 1 only
 (b) 2 and 3 only
 (c) 1 and 3 only
 (d) 1, 2 and 3

Solution: (c)
 Explanation:
 The Forest Carbon Partnership Facility (FCPF) is a global partnership of governments, businesses, civil society, and Indigenous Peoples. It supports REDD+ initiatives by providing financial and technical assistance to countries in their efforts to reduce emissions from deforestation and forest degradation.

However, it does not provide financial aid to universities, private scientists, or institutions for research purposes.

Q50. The Genetic Engineering Appraisal Committee is constituted under the [UPSC CSE Pre. 2015]

(a) Food Safety and Standards Act, 2006
 (b) Geographical Indications of Goods (Registration and Protection) Act, 1999
 (c) Environment (Protection) Act, 1986
 (d) Wildlife (Protection) Act, 1972

Solution: (c)
 Explanation:
The Genetic Engineering Appraisal Committee (GEAC) is constituted under the Environment (Protection) Act, 1986 and operates under the Ministry of Environment, Forest and Climate Change (MoEF&CC). It is responsible for appraising activities that involve hazardous microorganisms, genetic engineering research, and large-scale industrial applications. It also evaluates proposals for the release of genetically engineered organisms into the environment, including field trials.

Q51. If a wetland of international importance is brought under the 'Montreux Record,' what does it imply? [UPSC CSE Pre. 2014]

(a) Changes in ecological character have occurred, are occurring, or are likely to occur in the wetland as a result of human interference.
 (b) The country in which the wetland is located should enact a law to prohibit any human activity within five kilometers from the edge of the wetland.
 (c) The survival of the wetland depends on the cultural practices and traditions of certain communities living in its vicinity, and therefore the cultural diversity therein should not be destroyed.
 (d) It is given the status of 'World Heritage Site.'

Solution: (a)
 Explanation:
 The Montreux Record is a register of wetland sites listed under the Ramsar Convention where changes in ecological character have occurred, are occurring, or are likely to occur due to technological developments, pollution, or other human interference.

Q52. With reference to 'Eco-Sensitive Zones,' which of the following statements is/are correct? [UPSC CSE Pre. 2014]

1. Eco-Sensitive Zones are the areas that are declared under the Wildlife (Protection) Act, 1972.
2. The purpose of the declaration of Eco-Sensitive Zones is to prohibit all kinds of human activities in those zones except agriculture.

Select the correct answer using the code given below:
 (a) 1 only
 (b) 2 only
 (c) Both 1 and 2
 (d) Neither 1 nor 2

Solution: (d)
 Explanation:
 Eco-Sensitive Zones (ESZs) are declared under the Environment (Protection) Act, 1986, not the Wildlife (Protection) Act, 1972. The purpose of ESZs is to regulate and not prohibit activities. Permitted activities may include eco-tourism, organic farming, and renewable energy projects, while harmful activities like commercial mining and industrial pollution are restricted.

Q53. Consider the following pairs: [UPSC CSE Pre. 2014]

Wetlands	Conference of Rivers
1. Harike Wetlands	Confluence of Beas and Sutlej
2. Keoladeo Ghana National Park	Confluence of Banas and Chambal
3. Kolleru Lake	Confluence of Musi and Krishna

Which of the above pairs is/are correctly matched?
 (a) 1 only
 (b) 2 and 3 only
 (c) 1 and 3 only
 (d) 1, 2 and 3

Solution: (a)
 Explanation:

• Harike Wetlands is correctly matched (Confluence of Beas and Sutlej).
• Keoladeo Ghana National Park is incorrectly matched; it is formed by the confluence of Gambhiri and Banganga rivers.
• Kolleru Lake is incorrectly matched; it is a freshwater lake between the Krishna and Godavari deltas, not the Musi and Krishna rivers.

Q54. Consider the following international agreements: [UPSC CSE Pre. 2014]

1. The International Treaty on Plant Genetic Resources for Food and Agriculture.
2. The United Nations Convention to Combat Desertification.
3. The World Heritage Convention.

Which of the above has/have a bearing on biodiversity?
 (a) 1 and 2 only
 (b) 3 only
 (c) 1 and 3 only
 (d) 1, 2 and 3

Solution: (d)
 Explanation:

• The International Treaty on Plant Genetic Resources for Food and Agriculture aims at the conservation and sustainable use of plant genetic resources for food security.
• The United Nations Convention to Combat Desertification (UNCCD) addresses land degradation and its impact on biodiversity.
• The World Heritage Convention (UNESCO) promotes long-term conservation of natural and cultural heritage sites, many of which are rich in biodiversity.

Thus, all three agreements have a direct impact on biodiversity.

Q55. Consider the following statements regarding 'Earth Hour' [UPSC CSE Pre. 2014]

1. It is an initiative of UNEP and UNESCO.
2. It is a movement in which participants switch off the lights for one hour on a certain day every year.
3. It is a movement to raise awareness about climate change and the need to save the planet.

Which of the statements given above is/are correct?
 (a) 1 and 3 only
 (b) 2 only
 (c) 2 and 3 only
 (d) 1, 2 and 3

Solution: (c)
 Explanation:

• Statement 1 is incorrect because Earth Hour is organized by the World Wide Fund for Nature (WWF), not UNEP or UNESCO.
• Statement 2 is correct—it is an annual event where participants switch off lights for one hour on the last Saturday of March.
• Statement 3 is correct—the movement aims to raise awareness about climate change and encourage sustainable practices.

Q56. With reference to the Bombay Natural History Society (BNHS), consider the following statements: [UPSC CSE Pre. 2014]

1. It is an autonomous organization under the Ministry of Environment and Forests.
2. It strives to conserve nature through action-based research, education, and public awareness.
3. It organizes and conducts nature trails and camps for the general public.

Which of the statements given above is/are correct?
 (a) 1 and 3 only
 (b) 2 only
 (c) 2 and 3 only
 (d) 1, 2 and 3

Solution: (c)
 Explanation:

• Statement 1 is incorrect—BNHS is not an autonomous body under the Ministry of Environment and Forests; it is an independent NGO.
• Statements 2 and 3 are correct—BNHS focuses on nature conservation, public education, and field research and actively organizes nature trails and camps.

Q57. With reference to the 'Global Environment Facility,' which of the following statements is/are correct? [UPSC CSE Pre. 2014]
(a) It serves as a financial mechanism for the 'Convention on Biological Diversity' and the 'United Nations Framework Convention on Climate Change.'
(b) It undertakes scientific research on environmental issues at a global level.
 (c) It is an agency under the OECD to facilitate the transfer of technology and funds to underdeveloped countries with the specific aim of protecting their environment.
 (d) Both (a) and (b)

Answer: (a)
 Explanation:
 The Global Environment Facility (GEF) serves as a financial mechanism for multiple international environmental conventions, including the Convention on Biological Diversity (CBD) and the United Nations Framework Convention on Climate Change (UNFCCC). However, it is not an agency of the OECD and does not engage in direct scientific research.

Q58. With reference to the conservation organization called 'Wetlands International,' which of the following statements is/are correct? [UPSC CSE Pre. 2014]

1. It is an intergovernmental organization formed by countries that are signatories to the Ramsar Convention.
2. It works at the field level ttergoverno develop and mobilize knowledge and uses practical experience to advocate for better policies.

Select the correct answer using the code given below:
 (a) 1 only
 (b) 2 only
 (c) Both 1 and 2
 (d) Neither 1 nor 2

Answer: (b)
 Explanation:
 Wetlands International is a global, independent, not-for-profit organization dedicated to the conservation and restoration of wetlands. It is not an intergovernmental body but works at the ground level to mobilize knowledge and advocate for wetland conservation policies.

Q59. Consider the following statements: [UPSC CSE Pre. 2014]

1. The Animal Welfare Board of India is established under the Environment (Protection) Act, 1986.
2. The National Tiger Conservation Authority is a statutory body.
3. The National Ganga River Basin Authority is chaired by the Prime Minister.

Which of the statements given above is/are correct?
 (a) 1 only
 (b) 2 and 3 only
 (c) 2 only
 (d) 1, 2 and 3

Answer: (b)
 Explanation:

• The Animal Welfare Board of India was established under the Prevention of Cruelty to Animals Act, 1960, not the Environment (Protection) Act, 1986.
• The National Tiger Conservation Authority (NTCA) is a statutory body, established under an amendment to the Wildlife (Protection) Act, 1972, in 2006.
• The National Ganga River Basin Authority (NGRBA) is chaired by the Prime Minister of India.

Q60. Consider the following protected areas: [UPSC CSE Pre. 2014]

1. Bandipur
2. Bhitarkanika
3. Manas
4. Sundarbans

Which of the above are declared Tiger Reserves?
 (a) 1 and 2 only
 (b) 1, 3 and 4 only
 (c) 2, 3 and 4 only
 (d) 1, 2, 3 and 4

Answer: (b)
 Explanation:

• Bandipur (Karnataka), Manas (Assam), and Sundarbans (West Bengal) are designated Tiger Reserves under the Project Tiger initiative.
• Bhitarkanika (Odisha) is a national park and a Ramsar site but is not a Tiger Reserve.

Q61. In which one of the following categories of protected areas in India are local people not allowed to collect and use biomass? [UPSC CSE Pre. 2014]
(a) Biosphere Reserves
(b) National Parks
 (c) Wetlands declared under the Ramsar Convention
 (d) Wildlife Sanctuaries

Answer: (b)
 Explanation:
 National Parks have the highest level of protection among protected areas. In these areas, human activities such as biomass collection, grazing, and private tenurial rights are strictly prohibited. Biosphere Reserves, Wildlife Sanctuaries, and Ramsar wetlands may allow restricted human activity based on specific regulations.

Q62. With reference to the wetlands of India, consider the following statements: [UPSC CSE Pre. 2014]

1. The total geographical area under the category of wetlands is recorded as highest in Gujarat compared to other states.
2. In India, the total geographical area of coastal wetlands is larger than that of inland wetlands.

Which of the statements given above is/are correct?
 (a) 1 only
 (b) 2 only
 (c) Both 1 and 2
 (d) Neither 1 nor 2

Answer: (a)
 Explanation:

• Gujarat has the largest wetland area in India, contributing around 22.8% of the country's total wetland area.
• However, the total area of inland wetlands in India is greater than that of coastal wetlands. There are approximately 23,444 inland wetlands compared to 3,959 coastal wetlands.