Which best describes how sediment forms? a. loose material is compacted by pressure. b. chemical changes cause sediment to cement together. c. erosion breaks down rock and other material. d. molten rock cools below earth's surface.

Sediments are defined as solid fragments of inorganic or organic material. The bulk of sediment is formed from the weathering of rock, wherein the rock is broken into smaller and smaller pieces by a variety of chemical and mechanical processes, including acidic rainfall, freeze/thaw cycles, and the actions of organisms.

So I believe the answer is right let me know