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: electricity is used as an energy source by electrical devices, Fact2: Electrical fields result from electrical devices and televisions., Question: What is used as an energy source by television? (A) electricity (B) light (C) our nearest star (D) air (E) energy (F) satellites (G) photons (H) rocks
Example Output: A

Example Input: Fact1: Bivalves feed on plankton and nonliving organic matter., Fact2: Mussels are bivalve mollusks., Question: What feeds on plankton and nonliving organic matter? (A) barnacles (B) mollusks (C) animals (D) the Sun (E) sharks (F) graptolites (G) bacteria (H) dogs
Example Output: B

Example Input: Fact1: Chordates have a complete digestive system and a closed circulatory system., Fact2: Vertebrates are members of of a larger group, the chordates ., Question: vertebrates have a complete digestive system and a what? (A) Veins and arteries. (B) lack of backbone (C) bruised brain stem (D) critical organs (E) closed circulatory system (F) incomplete circulatory system (G) characteristics (H) sensory neurons
Example Output:
E