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: A student conducts an investigation using mold spores. In one part of the investigation, he needs to closely examine a spore sample. Which piece of equipment does the student need to use to keep mold spores from entering his respiratory system?  
 (A) breathing mask (B) safety goggles (C) rubber gloves (D) lead smock
Example Output: A

Example Input: Strong winds have the ability to uproot large trees in a wooded area. Which of these organisms would most likely benefit from this change in a habitat?  
 (A) a bee colony that needs a hive (B) a bird that needs to build a nest (C) a squirrel that needs to find shelter (D) a plant that needs sunlight to grow
Example Output: D

Example Input: Sterling silver is a combination of silver and copper. Which of the following is also a combination of two or more metals?  
 (A) aluminum. (B) lead. (C) gold. (D) brass.
Example Output:
D