Glaciers can only form when
a. there is an ice age.

b. there is a u-shaped valley in the mountains.

c. the amount of snow exceeds the amount of rain.

d. more snow falls than melts. glaciers can only form when

The right option is; D. more snow falls then melts

Glaciers can only form when more snow falls then melts.  

Glaciers are large thickened body of ice that is formed due to the compression of fallen snow over a long period of time.  Glaciers are formed when snow falls and the snow is positioned in one area for a long time which then melts and changes into ice. Glaciers have the ability to flow under its own mass, and it covers about 10 percent of the world’s land area.

it's c. (to reduce the greenhouse effect/carbon gasses)

true is the