Mass movement or mass wasting is a natural process in which the unstable sediments, stones, pebbles, debris moves down the slope under the effect of gravity. These materials are disturbed by physical agents such as water, wind and others. The mass movement is responsible for mudslides or landslides.
It should be option (A) because conduction is the transfer of heat energy from one place to another by vibrations/motion of the molecules. I hoped I helped.
