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: Proxima Centauri is the closest star to the Sun. Which units do astronomers most often use for the distance between Earth and Proxima Centauri?  
 (A) miles (B) meters (C) light years (D) astronomical units

Output: C


Input: Consider Input: To which group does an animal belong if it lays eggs and has scales and gills?  
 (A) amphibian (B) bird (C) fish (D) reptile

Output: C


Input: Consider Input: Which unit of measurement describes an object's length?  
 (A) meter (B) kilogram (C) liter (D) degree


Output: A