Why is it incomplete to explain high population in the Ganga plain only through water?

Correct answer: Because fertile soil historical settlement and agriculture are also important

The high population of the Ganga Plain cannot be explained by water alone. Water is important for drinking, farming, transport, and daily life, but people also need productive land and opportunities to live successfully. The plain has generally fertile alluvial soil, suitable level land, long-established settlements, and strong agricultural activity. Historical development, towns, roads, and employment also influence where people settle. Population distribution is usually the result of several connected physical and human factors.

Option A is correct because it includes fertile soil, historical settlement, and agriculture along with the wider explanation. Options B and C are false because the Ganga Plain has water and has supported settlements for a long time. Option D is also false because population is not limited to mountains. The correct reasoning is therefore multi-causal rather than based on one resource.