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: Auroras occur where Earth's magnetosphere traps high-energy particles in which region of the atmosphere?  
 (A) troposphere (B) stratosphere (C) thermosphere (D) exosphere
Example Output: C

Example Input: Which disease is a result of abnormal cell division?  
 (A) AIDS (B) cancer (C) chicken pox (D) common cold
Example Output: B

Example Input: Which gas is given off by a plant during photosynthesis?  
 (A) oxygen (B) nitrogen (C) hydrogen (D) carbon dioxide
Example Output:
A