The correct option is B Rains caused when a warm and moist air mass meets a cool and dry air mass.
Cyclonic rains are caused when the warm moist air comes in contact with cool dry air. At the end of summer, the air above the water heats up and rises creating an area of low pressure. So, the high pressure cold air starts rushing in. When this cold air meets the warm air, it forms a high-speed spiral that rises up and causes rain along the coasts.