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: Population size influences the chances of a species surviving., Fact2: Each species lasts for a time, sometimes surviving to the present and sometimes going extinct., Question: what influences the chances of going extinct? (A) cloud cover (B) Population size (C) Pollution (D) Pesticides (E) rainfall (F) risky population (G) Climate change (H) the environment
A:
B