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.

Ex Input:
While Anna was testing a circuit, she dropped a light bulb. What is the safest thing Anna can do?  
 (A) get a new bulb to finish the test (B) push the broken glass under a table (C) tell her teacher that she broke the bulb (D) ask her partner to help pick up the broken glass

Ex Output:
C


Ex Input:
What is the primary function of white blood cells in humans?  
 (A) carry oxygen (B) fight disease (C) grow tissues (D) remove waste

Ex Output:
B


Ex Input:
Environmental organizations have asked businesses to take action to reduce waste. Which of the following changes could a business make in order to become more “environmentally friendly”?  
 (A) Purchase only recycled paper and paper products. (B) When making photocopies, print on only one side of the paper. (C) Purchase wood products manufactured only in other countries. (D) When packing boxes, use Styrofoam™ filler instead of old newspapers.

Ex Output:

A