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: the Earth revolving around the Sun causes the seasons to change on its axis, Fact2: Winter is a horrible season., Question: What is a cause of the Earth revolving around the Sun? (A) heat (B) wind (C) winter (D) Light (E) Movement (F) energy (G) sunlight (H) Joules
C