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").
Q: Fact1: if the amount of available food and water decreases in an environment then animals may leave that environment to find food and water, Fact2: Many animals migrate, traveling to avoid bad weather, to find food, or to reproduce., Question: When food and water decreases, what increases? (A) energy usage (B) heat energy (C) Migration (D) Temperature (E) Pollution (F) forces (G) root growth (H) deforestation
A:
C