UPSC Prelims 2021— Question 43

In the Indus drainage, the Jhelum, Ravi and Chenab ultimately feed into the Sutlej system before the combined flow reaches the Indus; the Sutlej itself joins the Indus downstream. Hence among the listed rivers, Sutlej is the direct tributary to the Indus. The question is designed to distinguish the internal tributary sequence from the final confluence. The final answer-key position for Set C identifies option D as the correct option. Option A — Chenab — 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 B — Jhelum — 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 — Ravi — 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 — Sutlej — is correct because it is the alternative that matches the constitutional, historical, geographical, scientific or economic principle established above. 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.