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

Example Input: A rubber band will make a sound when it is  
 (A) vibrated. (B) stretched. (C) cut into pieces. (D) shot across a room.
Example Output: A

Example Input: Scientists working for a company are testing a new medicine that they think will help heal damaged tissue. In which part of the company are the scientists working?  
 (A) distribution (B) mass marketing (C) public relations (D) research
Example Output:
D