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").

Ex Input:
Fact1: tidal energy can be used to produce electricity, Fact2: Tidal caves are formed by the energy of the rising and falling tides., Question: what can produce electricity? (A) rivers (B) animal transport (C) tidal caves (D) Nematoda (E) rays or beams (F) animals (G) cactuses (H) photons

Ex Output:
C

Ex Input:
Fact1: melting means changing from a solid into a liquid by adding heat energy, Fact2: Ice is the solid form of water., Question: What changes ice to water by adding heat energy? (A) mussels (B) melting (C) freezing (D) fertilization (E) storms (F) boiling (G) engines (H) condensation

Ex Output:
B

Ex Input:
Fact1: Trees have woody stems covered with bark., Fact2: An elm tree is a type of tree that grows in America., Question: what have woody stems covered with bark? (A) bushes (B) h2o (C) elms (D) roses (E) oak (F) dogs (G) Spruce (H) bamboo

Ex Output:
C