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: When a hammer strikes a nail, the nail
(A) exerts balanced forces that helps it from moving. (B) exerts a force equal to the weight of the hammer. (C) exerts an unbalanced force that changes its velocity. (D) exerts an equal and opposite force back on the hammer.
Example Output: D

Example Input: In some locations, squirrels sleep for long periods of time during the winter months. Which of the following most likely causes these squirrels to sleep for long periods of time?
(A) increase in humidity (B) decrease in temperature (C) clouds forming in the sky (D) winds blowing in the night
Example Output: B

Example Input: What is the main difference between planets and moons in our solar system?
(A) All planets can support life; moons cannot. (B) All planets have atmospheres; moons do not. (C) All planets orbit the Sun; all moons orbit planets. (D) All planets are larger than all moons.
Example Output:
C