Explanation : 

Statement 1 & 2: Scientists estimate that roughly half of the oxygen production on Earth comes from the ocean. The majority of this production is from oceanic plankton — drifting plants, algae, and some bacteria that can photosynthesize. One particular species, Prochlorococcus, is the smallest photosynthetic organism on Earth.
Source : https://oceanservice.noaa.gov/facts/ocean-oxygen.html

Statement 3 : Well-oxygenated surface water may only contain around 8 mg O₂/l, while the air contains 210 mg O₂/l.

Explanation : 

I. Cassava : Woody shrub Cassava (Manihot esculenta) is a woody shrub. It is a perennial shrub with woody stems. Thus, this pair is correctly matched.

II. Ginger : Herb with pseudostem Ginger (Zingiber officinale) is a herbaceous perennial plant characterized by a pseudostem formed by rolled leaf bases. Thus, this pair is correctly matched.

III. Malabar spinach : Herbaceous climber Malabar spinach (Basella alba) is a fast-growing, soft-stemmed, herbaceous climbing vine. Thus, this pair is correctly matched.

IV. Mint : Annual shrub Mint (Mentha spp.) is a perennial herbaceous plant, not an annual shrub. It does not have woody stems and typically grows back each year from underground rhizomes. Thus, this pair is incorrectly matched.

V. Papaya : Woody shrub Papaya (Carica papaya) is generally considered a large herbaceous plant or small tree-like herb, not a woody shrub. It has a soft, hollow, herbaceous stem rather than a woody stem. Thus, this pair is incorrectly matched.

Correct matches are:

• Cassava (correct)
• Ginger (correct)
• Malabar spinach (correct)
• Mint (incorrect)
• Papaya (incorrect)

Therefore, correct answer is option (b) Only three.

Explanation : 

I. Carbon dioxide (CO2) emissions in India are less than 0.5 t CO2/capita.

This statement is incorrect. In 2023, India’s per capita emissions were around 2 tonnes, 2.05 metric tons of CO2 equivalent, or 2.9 tons of CO2 equivalent (tCO2e).

II. In terms of CO2 emissions from fuel combustion, India ranks second in Asia-Pacific region.
This statement is correct. According to the International Energy Agency (IEA) data for 2022, in the Asia-Pacific region, China ranks first in CO2 emissions from fuel combustion, followed by India in second place, and Japan in third.

III. Electricity and heat producers are the largest sources of CO2 emissions in India.

This statement is correct. The energy sector is the largest contributor to India’s overall greenhouse gas emissions, accounting for 75.66% in 2020. Within the energy sector, power generation (electricity and heat producers) is consistently identified as the primary source of CO2 emissions, contributing approximately 45% of the total energy emissions in 2018. Industries are the second largest contributor, with a share of about 25%.

Explanation : 

1. It is an omnivorous crustacean.
   Incorrect. The Peacock tarantula (Poecilotheria metallica) is an arachnid, specifically a spider, not a crustacean. Crustaceans include animals like crabs, lobsters, and shrimp. Furthermore, tarantulas are carnivorous, meaning they primarily eat other animals (insects, small rodents, etc.), not plants and animals (omnivorous).
2. Its natural habitat in India is only limited to some forest areas.
   Correct. The Peacock tarantula is critically endangered and has a very restricted natural habitat. It is endemic to a small, specific forest area in the Eastern Ghats of Andhra Pradesh, India. Its known range is extremely limited to a small reserve forest.
3. In its natural habitat, it is an arboreal species.
   Correct. “Arboreal” means living in trees. The Peacock tarantula is known to live in tree holes and crevices in its natural forest habitat, making it an arboreal species.

Explanation : 

Direct Air Capture (DAC)

Direct Air Capture (DAC) pulls CO₂ straight from ambient air using chemical sorbents or solvents.

I. True – Once captured, the CO₂ can be sequestered underground (geological storage) or mineralized, making DAC a carbon-removal technology.

II. True – The purified CO₂ stream can serve as a feedstock for making polymers (e.g. polyurethanes, polycarbonates) and in food-processing (carbonation, modified-atmosphere packaging, microbial fermentations).

III. True – Captured CO₂ can be combined with green hydrogen (from renewables) in Fischer–Tropsch or related processes to produce synthetic “e-fuels,” including drop-in aviation fuels.

Explanation : 

Asian Development Bank (ADB)

Asian Development Bank (ADB) launched the “Nature Solutions Finance Hub for Asia and the Pacific” to support countries in the region in mobilizing finance for nature-based solutions. This initiative aims to address climate change, biodiversity loss, and environmental degradation by promoting sustainable investments and projects that leverage natural ecosystems.

Explanation : 

Article 6 of the Paris Agreement

Article 6 of the Paris Agreement is the only place in the Agreement that lays out rules for Parties to “cooperate” in meeting their Nationally Determined Contributions – and it does so in two complementary ways:

1. Market-based cooperation (Articles 6.2 & 6.4) – Establishes the framework for the internationally transferred mitigation outcomes (ITMOs) and the new “Sustainable Development Mechanism,” i.e. a UN-supervised carbon-market mechanism. – ⇒ Statement II.

2. Non-market approaches (Article 6.8) – Encourages Parties to work together on mitigation, adaptation, finance, technology transfer and capacity building without creating tradeable credits – i.e. “non-market” forms of cooperation across borders. – ⇒ Statement III

Because both the market and the non-market strands of Article 6 are debated (they underpin the only mechanisms in the Paris text for cooperative implementation), Statements II and III are both correct—and together they explain why Article 6 is so frequently discussed (Statement I).

Correct : https://unfccc.int/process/the-paris-agreement/cooperative-implementation

Explanation : 

– Statement II is correct: powerful solar flares and coronal-mass ejections do indeed slam into and energize Earth’s outer atmosphere (the thermosphere and magnetosphere).

– Statement III is correct: as polar ice melts, the freed water mass is redistributed toward lower latitudes (i.e. toward the equator), altering the planet’s moment of inertia.

Only Statement III provides a mechanism for the observed change in Earth’s rotation‐axis and length‐of‐day (mass moving away from the poles slows Earth’s spin and shifts the instantaneous pole).

Solar storms, although energetic, have only a negligible net effect on the solid‐Earth rotation. Hence both II and III are true, but only III explains Statement I.

Explanation : 

COP28 Declaration on Climate and Health

Statement I –  India, along with the United States, did not sign the COP28 Declaration on Climate and Health.

Statement II – The COP28 Declaration on Climate and Health is a non-binding, non-negotiated call to action and collective commitment that reflects the concerns and common position of countries on the importance of health within climate discourse and in the COP process. It begins to articulate how climate-health is defined and how parties come together to address the urgent need for integrating climate and health.

Statement III – India, a nation grappling with significant healthcare challenges, including those exacerbated by climate change, expressed concerns that greenhouse gas reduction for cooling in the health sector could hinder its ability to meet the growing demands for medical services, particularly in remote and underserved areas, a delegate from Kenya said.

Explanation : 

Statement I is true – cement manufacture is responsible for roughly 5–7 % of global CO₂ emissions.

Statement II is true – Portland‐cement “raw meal” is typically made by grinding together about 80 % limestone (CaCO₃) with 20 % silica-bearing clays and other minor additives.

Statement III is true – in the kiln the limestone is calcined: CaCO₃ → CaO + CO₂↑

Of the two, only Statement III explains the CO₂ emissions in Statement I (the chemical decomposition of CaCO₃ releases CO₂). Statement II describes the raw‐material blend but does not itself generate CO₂. Hence both II and III are correct, but only III explains I.