The pressure differences that make wind happen are caused
A. by a sudden drop in humidity.
B. when water vapor in the air rises then falls.
C. by accumulations of clouds in different areas.
D. by the unequal heating of Earth’s surface.

Question

The pressure differences that make wind happen are caused
	A. by a sudden drop in humidity. 	
	B. when water vapor in the air rises then falls. 	
	C. by accumulations of clouds in different areas. 	
	D. by the unequal heating of Earth’s surface.

anonymous · Answer

D. by the unequal heating of Earth’s surface.