Which of the Following Best Describes the Climatic Factors That

Which of the following best describes the climatic factors that cause low latitude deserts like the Sahara in Africa?

A) Warm, humid air aloft is descending; surface winds blow away from the equator.
B) Warm, humid air is rising; surface winds are calm.
C) Cool, dry air at the surface is rising causing winds to blow away from the equator.
D) Cool, dry air aloft is descending; surface winds are blowing toward the equator.