You are given a science question (easy-level) and four answer options (associated with "A", "B", "C", "D"). Your task is to find the correct answer based on scientific facts, knowledge, and reasoning. Do not generate anything else apart from one of the following characters: 'A', 'B, 'C', 'D'. There is only one correct answer for each question.

Example Input: When do mutations help make an ecosystem more sustainable?  
 (A) when mutations decrease the number of individuals in an ecosystem (B) when mutations increase the number of individuals in an ecosystem (C) when mutations decrease the number of species in an ecosystem (D) when mutations increase the number of species in an ecosystem
Example Output: D

Example Input: Most of the United States is a part of which tectonic plate?  
 (A) Pacific Plate (B) Eurasian Plate (C) North American Plate (D) South American Plate
Example Output: C

Example Input: There is a thunderstorm close to your house. The windows rattle at the same time that you hear the thunder. What causes the windows to rattle?  
 (A) Sound waves from the thunder (B) Light from the lightning (C) Rain from the clouds (D) The high humidity during the storm
Example Output:
A