The correct answer is: a) Southwest monsoon (June-September).
The Southwest monsoon is the prevailing wind direction during the summer monsoon season in the Indian subcontinent. It blows from the southwest towards the northeast, bringing heavy rains to the region. The monsoon season is from June to September, and the heaviest rains usually fall in July and August.
The Northeast monsoon is the prevailing wind direction during the winter monsoon season in the Indian subcontinent. It blows from the northeast towards the southwest, bringing dry weather to the region. The winter monsoon season is from October to December, and the driest months are usually November and December.
The winter months are from December to February, and they are the coldest months of the year in the Indian subcontinent. The weather is dry and sunny, with little rainfall.
Rainfall is evenly distributed throughout the year in some parts of the world, such as the equatorial regions. However, in most parts of the world, rainfall is seasonal, with most of the rain falling during one particular season. In the Indian subcontinent, the Southwest monsoon is the main source of rainfall.