Q: 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: the surface of a beach is formed by mechanical weathering, Fact2: Most beaches are of white coral sand., Question: What action produces much of the sand from coral? (A) reef building (B) radioactive decay (C) mechanical waves (D) glass blowing (E) It used to be covered by water (F) The area was once underwater (G) Mechanical weathering (H) By coral exoskeletons
A:
G