Help please happens when gravity moves sediment downhill.

a. Weathering only
b. Mass movement
c. Erosion only
d. Gravity

B

Explanation:

A mass movement denotes a political party or movement which is supported by large segments of a population. Political movements that typically advocate the creation of a mass movement include the ideologies of communism, fascism, and liberalism. Both communists and fascists typically support the creation of mass movements as a means to overthrow a government and create their own government, the mass movement then being used afterwards to protect the government from being overthrown itself; whereas liberals seek mass participation in the state apparatus of representative democracy.

B. Mass movement

Explanation:

Gravity can cause erosion and deposition. Gravity makes water and ice move. It also causes rock, soil, snow, or other material to move downhill in a process called mass movement.