The correct answer is C. glacier.
A glacier is a large mass of ice that forms over land and moves slowly downslope under the force of gravity. Glaciers are found in many parts of the world, including the polar regions, high mountains, and some temperate regions.
Glaciers are formed when snow accumulates over many years and becomes compacted into ice. The weight of the ice causes the glacier to flow downhill, and the ice is also lubricated by meltwater that forms at the base of the glacier.
Glaciers are important because they help to shape the landscape. They also play a role in the water cycle, as they melt and release water into rivers and streams.
A. delta is a landform that forms at the mouth of a river where the river meets the ocean. Deltas are made up of sediment that is carried by the river and deposited at the mouth of the river.
B. watershed is an area of land that drains into a particular river or stream. Watershed boundaries are determined by the elevation of the land.
D. crevasses are large cracks that form in glaciers. Crevasses are caused by the movement of the glacier and the stress that is placed on the ice.