You will be given a definition of a task first, then some input of the task.
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").

Fact1: condensing means changing from a gas into a liquid by reducing heat energy, Fact2: Condensation involves molecules joining together with the release of water., Question: What results in changing from a gas into a liquid by reducing heat energy? (A) exposure to cold (B) degrees celcius (C) molecules joining together (D) rain or sun shine (E) Warm air moving into cold air (F) molecules separating (G) molecules becoming nothing (H) molecules exploding
Output:
C