Akind of sedimentary rock formed from plant material over a long period of time is

a. limestone

b. cementation

c. coal

d. compaction

The correct answer is:

c. coal

Explanation:

Coal is a fossil fuel that forms when dead plant material is remodeled into peat, which in turn is transformed into lignite, then sub-bituminous coal, after that bituminous coal, and lastly anthracite. Most of the coal we use now was formed about 300 million years ago, when much of the earth was inundated by humid swamps. As plants and trees died, their remains sank to the bottom of the swampy areas, creating layers and layers of plant material and sequentially forming a soggy, thick material called PEAT.