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 describes a material that is not a food?  
 (A) It stores energy but not nutrients. (B) It does not store energy or nutrients. (C) It stores energy and nutrients. (D) It does not store energy but stores nutrients.
Example Output: B

Example Input: The changing appearances of the nighttime sky over the surface of Earth and eclipses of the Moon have provided evidence that  
 (A) Earth is a sphere. (B) Earth supports life. (C) Earth has a layered atmosphere. (D) Earth is covered mostly with water.
Example Output: A

Example Input: A student finds a round, smooth pebble on a beach. Which action made the pebble smooth?  
 (A) rain falling (B) wind blowing (C) snow melting (D) waves moving
Example Output:
D