Final answer:
The southwest monsoon picks up moisture from the Arabian Sea, Bay of Bengal, and Indian Ocean. Therefore, the correct option is A.
Step-by-step explanation:
The correct set of water bodies from which the southwest monsoon picks up moisture is (a) Arabian Sea, Bay of Bengal, Indian Ocean. The southwest monsoon is characterized by warm moist air being pulled in from the Arabian Sea, Bay of Bengal, and Indian Ocean, which then moves over the land, leading to heavy rainfall in South Asia during the monsoon season. This moisture contributes to the rivers and streams that flow into major rivers like the Brahmaputra, Ganges, and Indus in South Asia.