Assertion (A): Areas lying within five to eight degrees latitude on either side of the equator receive rainfall throughout the year. Reason (R): High temperatures and high humidity cause convectional rain to fall mostly in the afternoons near the equator.

The equatorial region, extending roughly 5 to 10 degrees north and south of the equator, is characterized by high temperatures and significant evaporation throughout the year. This intense solar heating causes the air to rise in a continuous process known as convection. As this warm, moist air ascends, it cools and condenses, leading to heavy rainfall. Because this process occurs daily due to the consistent heat and humidity, these areas receive rainfall year-round, typically in the late afternoon. Therefore, the assertion is a true statement about the climate of this belt, and the reason provided accurately explains the physical process of convectional rainfall that causes it. This makes Option A the correct answer.