Question

this is the transport (movement) of fragments of rock by water, wind, ice, or gravity. terracing glaciers landslide erosion

Explanation:

The question describes the movement of rock fragments by water, wind, ice, or gravity. Terracing is a farming practice to prevent erosion. Glaciers are a form of ice, not the process of moving rock. Landslide is a sudden movement of rock/soil due to gravity, but the definition here is broader (includes water, wind, etc.). Erosion is the process of transporting rock fragments by these agents.

Answer:

erosion