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: Consider Input: Fact1: a prism is used for refracting light, Fact2: Refraction is the bending of light cause by a speed change when it passes through different media., Question: What aspect of light changes when it passes from air into a prism? (A) power (B) seasons (C) speed (D) energy (E) a wave (F) Joules (G) heat (H) unique

Output: C


Input: Consider Input: Fact1: if a neutral atom loses an electron then an atom with a negative charge will be formed, Fact2: If an atom loses an electron, it is then positive., Question: what can an atom be? (A) Energy. (B) energy (C) microscopic (D) dangerous (E) small (F) nucleus (G) an object (H) negative

Output: H


Input: Consider Input: Fact1: Mutations are essential for evolution to occur., Fact2: Mutations Mutations are caused by random changes in genes., Question: what is essential for evolution to occur? (A) random changes in genes (B) that material's properties (C) cancer (D) remains of prehistoric life (E) h2o (F) Plant reproduction (G) revolutions (H) the environment


Output: A