Which of these types of mass movements is the fastest and least depended upon moist or saturated conditions?
a. solifluction
b. rock fall
c. rock slide
d. soil creep
e. talus creep

Option (B)

Explanation:

A rockfall is defined as a type of mass movement process, where the small and large fragments of rocks are weathered and fall down from the top of the cliff under the influence of gravity. It is a process that takes place in a dry condition. This means that it does not depend on the moisture content that could be present in the rock. The rock particles fall down by bouncing and rolling. The base of this rockfall area forms a collection of smaller to larger size rock fragments. This process mainly takes place in the region where the temperature of the area is very high and experiences comparatively less amount of rainfall.

Thus, this type of mass movement is the fastest of all and is not dependent on the amount of moisture content.

Thus, the correct answer is option (B).