How do prevailing winds control precipitation totals in a region? Select 3 correct choices or none of the above.

a. They cause oceanic winds to carry water vapor.
b. They move warm air masses in certain directions.
c. They increase the occurrence of droughts in the winter.
d. They reduce rainfall on the leeward side of a mountain.
e. They affect the movement of winds that come from oceans.
f. none of the above