The correct answer is: A. Bay of Bengal branch.
The Bay of Bengal branch of the Indian monsoon is the dominant monsoonal wind system that affects the state of Chhattisgarh. The monsoonal winds blow from the southwest during the summer months, bringing heavy rainfall to the state. The Bay of Bengal branch of the monsoon is responsible for more than 80% of the annual rainfall in Chhattisgarh.
The Arabian Sea branch of the Indian monsoon is a secondary monsoonal wind system that affects the state of Chhattisgarh. The Arabian Sea branch of the monsoon is responsible for less than 20% of the annual rainfall in Chhattisgarh.
The Indian Ocean branch of the Indian monsoon is a tertiary monsoonal wind system that affects the state of Chhattisgarh. The Indian Ocean branch of the monsoon is responsible for less than 1% of the annual rainfall in Chhattisgarh.
The retreating monsoon is a seasonal wind system that affects the state of Chhattisgarh during the winter months. The retreating monsoon blows from the northeast, bringing dry weather to the state. The retreating monsoon is not a significant source of rainfall in Chhattisgarh.