Answer: B

Explanation:

The 2026 Nobel Prize in Chemistry was awarded to French scientist Henri B. Kagan and Japanese chemist Kenso Soai on October 7, 2026.

The Royal Swedish Academy of Sciences recognized the duo "for the discovery of non-linear effects and autocatalysis in asymmetric organic synthesis". Their revolutionary work solved a century-old chemical mystery by detailing how chemical reactions can generate and amplify asymmetry in "mirror image" molecules, a phenomenon known as molecular chirality or homochirality.

Answer: C

Explanation:

Statement 1 — Correct: Chirality is a molecular property associated with handedness. Two mirror-image forms of a chiral molecule are called enantiomers. They often behave differently in biological systems.

Statement 2 — Correct: A non-linear effect arises when the relationship between the enantiomeric composition of a chiral catalyst and the product is not linear. Depending on the reaction mechanism, the product may have a higher or lower enantiomeric excess than the catalyst.

Statement 3 — Incorrect: Asymmetric catalysis is specifically used to favour the formation of one enantiomer over the other. It does not necessarily produce a 50:50 mixture.

Statement 4 — Correct: Certain catalytic systems can amplify a small initial imbalance between two mirror-image forms, helping explain how high enantiomeric enrichment can arise.

Answer: C

Explanation:

Statement 1 is incorrect: The Living Planet Index (LPI) does not measure the absolute number of individual animals that have gone extinct or been lost. Instead, it tracks the average change in relative abundance (increase or decrease) of monitored vertebrate population sizes over time. A 73% average decline means population sizes shrunk on average, not that 73% of species are extinct.

Statement 2 is correct: According to the 2026 report, freshwater ecosystems suffered the steepest drop with an 85% average decline, far outpacing terrestrial ecosystems (69%) and marine ecosystems (59%).

Statement 3 is correct: The Living Planet Index is developed and produced by the Zoological Society of London (ZSL) in partnership with the World Wide Fund for Nature (WWF).

Answer: B

Explanation:

Pair 1 is correctly matched: The 2026 report highlights a 73% average decline in monitored vertebrate populations (mammals, birds, fish, amphibians, and reptiles) between 1970 and 2022.

Pair 2 is correctly matched: Regionally, Latin America and the Caribbean experienced the most catastrophic drop, witnessing a 95% average decline in wildlife populations.

Pair 3 is incorrectly matched: While climate change is a major driver, the report explicitly identifies the global food system (the way the world produces and consumes food) as the single largest driver of biodiversity loss, alongside habitat destruction and overexploitation.

Answer: A

Explanation:

Statement 1 is correct: Article 262(1) of the Indian Constitution states that Parliament may by law provide for the adjudication of any dispute or complaint with respect to the use, distribution, or control of the waters of, or in, any inter-state river or river valley.

Statement 2 is correct: The Inter-State River Water Disputes (ISRWD) Act, 1956 was enacted by Parliament under Article 262 to set up ad-hoc tribunals for resolving disputes when negotiated settlements fail.

Statement 3 is incorrect: Article 262(2) explicitly allows Parliament to enact a law providing that neither the Supreme Court nor any other court shall exercise jurisdiction in respect of any such dispute or complaint. Under the ISRWD Act, the jurisdiction of ordinary courts, including the Supreme Court's original jurisdiction under Article 131, is barred with respect to matters referred to a tribunal (though the Supreme Court retains limited appellate/special leave jurisdiction over the tribunal's final award).