Definition: 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").
Input: Fact1: hearing is used for sensing sound by animals, Fact2: Hearing requires functioning ears., Question: What are used for sensing sounds by animals? (A) ears (B) echolocation (C) birds (D) fibers (E) toads (F) the nose (G) Frogs. (H) the blood
Output:
A