Definition: 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: Fact1: melting means changing from a solid into a liquid by adding heat energy, Fact2: When a substance melts, it changes phase from a solid to a liquid by the application of heat., Question: What can be done to a solid by adding heat energy? (A) massive damage (B) phasing the bubbles (C) It expands (D) cooling the center (E) Evaporation (F) changing the phase (G) removing the air (H) Water expanding
Output:
F