Answer:
B. At the edge of the plates
Explanation:
Gravity is the principal driving force of plate tectonics (second one is convection). It causes different density plates to move on the Earth's surface. However, when a denser plate coincides the less denser plate, the high density plate subducts below the lesser density plate. The process, therefore, is called subduction. During this collision of plates, shearing resistance increases and all pressures come at the edge of the plate. The process continues and the lithosphere drags the rest of the plate. The portion of plate below the less denser plate then reaches the mantle. Here, the edge of plate is destroyed due to high temperature of mantle as well as pressure.
