Given the task definition and input, reply with output. 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: Temperature falls from lower to higher altitudes., Fact2: If the weather is warm, their temperature rises., Question: What falls from lower to higher altitudes? (A) warm weather (B) sun's heat (C) rainfall (D) heat energy (E) kinetic energy (F) water vapor (G) colder and wetter (H) Greenhouse gasses
A