In this task, you are given two facts, and a multiple-choice question. Based on the given facts, answer the question with index of the correct option (e.g, "A").

Fact1: decomposition increases amount of organic matter in soil, Fact2: Organic matter is the plant and animal residue in the soil at various stages of decomposition., Question: What decomposes in soil? (A) swamp vegetation (B) roundworms (C) Echinoids (D) tunicates (E) Earthworms (F) some invertebrates (G) most cephalopods (H) Plant and animals
H