01 What is it called when one plate sinks below another plate?
Answer and explanation
Correct answer: D. Subduction
Explanation: When one tectonic plate moves downward and sinks beneath another plate, the process is called subduction. It usually occurs at a convergent boundary, where plates move toward each other. The descending plate enters the mantle, and this movement can produce a deep ocean trench, earthquakes, and sometimes volcanic activity. Therefore, option D, subduction, is correct.
Divergence means plates moving apart, so it is not the process described here. Weathering is the breakdown of rocks at or near the surface, and deposition is the laying down of transported sediments. Neither describes a tectonic plate sinking beneath another. The Hindi term “अवगमन” and the English term “subduction” identify the same process. Connecting subduction with convergent boundaries and deep trenches is a useful way to remember the concept.