Why does the Arabian Sea branch of the south-west monsoon give heavy rainfall on the Western Ghats?

Correct answer: Because moist winds strike the mountains and rise

Answer: C. The Arabian Sea branch of the south-west monsoon travels over the Arabian Sea and collects a large amount of water vapour. When these moist winds reach the west coast, the Western Ghats form a barrier in their path. The air is forced to rise along the mountain slopes. As rising air expands and cools, the water vapour condenses into clouds and produces heavy orographic rainfall on the windward side. C is correct because it includes both essential steps: moist air is blocked by the mountains and is lifted upward. A is wrong because the branch comes mainly across the Arabian Sea, not from a dry land surface. B is wrong because this branch does not return from the Himalayas. D is wrong because sunlight is not the main reason for this rainfall; the decisive process is the forced rising and cooling of moist air. Memory cue: moisture plus mountain uplift equals orographic rain.