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: Which action does a kitten learn from its mother?  
 (A) how to grow (B) how to meow (C) how to hunt mice (D) how to nurse milk

Output: C


Input: Consider Input: Which unit is used to indicate the amount of energy in food?  
 (A) ounce (B) degree (C) calorie (D) gram

Output: C


Input: Consider Input: What can we learn by studying fossils?  
 (A) how hurricanes formed long ago (B) how the solar system was formed (C) the cause of strong earthquakes (D) how Earth's environments have changed


Output: D