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").

Example Input: Fact1: Infancy is the period of most rapid growth after birth., Fact2: During infancy, babies learn whether to trust the world., Question: Babies do what most during their rapid growth period? (A) birth (B) move (C) run (D) fight (E) puberty (F) play (G) learn (H) shaking
Example Output: G

Example Input: Fact1: All animals are heterotrophs., Fact2: Heterotrophic bacteria derive energy from the breakdown of organic molecules., Question: What derive energy from the breakdown of organic molecules? (A) Most plants (B) hydrocarbons (C) potatoes (D) all stones (E) all water sources (F) all mountains (G) all animals (H) Generating heat
Example Output: G

Example Input: Fact1: Biomass is the total mass of organisms at a trophic level., Fact2: Each of the steps in the food chain is a trophic level ., Question: Biomass is the total mass of organisms at a step in the what? (A) Energy (B) Plants growth (C) food chain (D) agriculture (E) Animal survival (F) Energy. (G) energy usage (H) kinetic energy
Example Output:
C