The correct answer is: d) All of the above.
The southwest monsoon winds are a seasonal wind that blows from the southwest to the northeast across the Indian subcontinent. They are caused by the difference in temperature between the land and the ocean. The land heats up faster than the ocean, which creates a low-pressure system over the land. This low-pressure system draws in moist air from the ocean, which rises and cools, causing the formation of clouds and rain.
The Bay of Bengal is a large bay in the Indian Ocean. It is located to the east of India and to the west of Myanmar. The Bay of Bengal is a major source of moisture for the southwest monsoon winds. The warm waters of the Bay of Bengal provide the energy for the monsoon winds, and the moisture from the Bay of Bengal is carried inland by the monsoon winds.
Orographic uplift is the process of air being forced upwards by mountains. As air rises, it cools and condenses, forming clouds and rain. The mountains of Mizoram force the southwest monsoon winds to rise, which causes the formation of clouds and rain.
Therefore, the heavy rainfall in Mizoram is influenced by the southwest monsoon winds, proximity to the Bay of Bengal, and orographic uplift.