Terrigenous sediment consists primarily of mineral grains eroded from

A. mid-ocean ridges.

B. marine animal shells.

C. continental rocks.

D. undersea minerals.

The answer is letter C.

Terrigenous sediments come from continental rocks, meaning they come from inland. The erosion of rocks from the environment (e. g. volcanic eruptions, rock weathering) causes the development of these sediments. These sediments may consist of sand, mud, and silt, that are usually carried to bigger bodies of water by rivers.