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.

Input: Consider Input: Genes are located on chromosomes which are composed of  
 (A) DNA. (B) RNA. (C) ATP. (D) ADP.

Output: A


Input: Consider Input: Many types of organisms live in a meadow. With the introduction of a large, swift-moving predator into the meadow ecosystem, which group of organisms will MOST likely have an advantage of surviving and reproducing?  
 (A) mice that have the thickest fur (B) foxes that have the largest ears (C) gophers that dig the deepest holes (D) rabbits that can run the fastest

Output: D


Input: Consider Input: What may form as a direct result of a star collapsing?  
 (A) constellation (B) galaxy (C) protostar (D) supernova


Output: D