UPSC Prelims 2021— Question 21

Water is a polar molecule with an uneven distribution of electrical charge, allowing it to interact with and dissolve many ionic and polar substances. Its high specific heat and heat-conduction properties do not explain its exceptional solvent capacity, and describing it merely as an oxide of hydrogen says nothing about the relevant intermolecular interactions. Dipolarity is therefore the key property. The final answer-key position for Set C identifies option A as the correct option. Option A — it is dipolar in nature — is correct because it is the alternative that matches the constitutional, historical, geographical, scientific or economic principle established above. Option B — it is a good conductor of heat — is not correct because it does not satisfy the specific condition tested in the question; it represents an alternative that is contradicted, incomplete, or less precise than the accepted answer. Option C — it has high value of specific heat — is not correct because it does not satisfy the specific condition tested in the question; it represents an alternative that is contradicted, incomplete, or less precise than the accepted answer. Option D — it is an oxide of hydrogen — is not correct because it does not satisfy the specific condition tested in the question; it represents an alternative that is contradicted, incomplete, or less precise than the accepted answer. For PYQ interpretation, the distinction between the correct alternative and merely related facts is important. UPSC often places plausible distractors beside the precise statement that matches the underlying rule, chronology, definition or empirical relationship. The answer should therefore be read against the exact wording of the question rather than against a broadly related fact.