During thisrocks fall because gravity and then build up at the base of the cliff

During mass wasting/mass movement rocks fall because gravity and then build up at the base of the cliff

Explanation:

Weathered materials are moved by forces of gravity from a higher place to a lower one.Some occurs sudden with adverse effects such as landslides while some movements are less dramatic such as slump and creep movements that move materials slowly to the bottom of a hillside.In mass wasting, weathered material experience less forces holding them causing them to fall to the base of a cliff forming a talus slope.

a:

by the combination of an unlimited number of elements