Instructions: 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: breathing is when a gill converts from oxygen in water into oxygen in blood, Fact2: Sharks breathe using gills., Question: What do sharks use to convert oxygen? (A) gills (B) skin (C) blood (D) fins (E) Enzymes (F) mouth (G) tail (H) fibers
Output:
A