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: a plant requires sunlight to grow, Fact2: Plants to avoid are fast-growing vines that can take over an area in no time., Question: What requires sunlight in order to take over an area? (A) spores (B) fish (C) plants (D) humans (E) pods (F) Oak (G) opossums (H) coral
Example output: C
Example explanation: This is a good example. Based on the facts plants require sunlight in order to take over an area.
Q: Fact1: Mammals generate heat mainly by keeping their metabolic rate high., Fact2: All humans are mammals., Question: what generates heat mainly by keeping their metabolic rate high? (A) humans (B) clouds (C) rabbit (D) bears (E) animals (F) the sun (G) insects (H) goats
A:
A