Why is map study important for understanding India's drainage system?

Correct answer: It helps identify source, direction, tributaries and mouth of rivers

The direct answer is A: maps help identify a river’s source, direction, tributaries and mouth. A drainage system is not just a single line; it includes the main river, smaller tributaries, the area drained and the final outlet. Step by step: a map shows where a river begins, or its source; arrows and the course show its direction; joining streams show tributaries; the place where it enters a sea, lake or another river is its mouth or confluence. Option A is correct because it includes the essential features needed to understand drainage. Option B is wrong because language is a cultural feature, not the main purpose of drainage maps. Option C is wrong because animal numbers require wildlife or population data. Option D is wrong because sea-wave height requires marine measurements, not ordinary river-system mapping. Exam cue: practise tracing source-to-mouth on an outline map.