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: In Maryland, most bears have thick, dark fur. Which statement best explains how dark fur helps bears survive in the forests of Maryland?  
 (A) Dark fur is lightweight. (B) Dark fur scares enemies. (C) Dark fur helps bears hide. (D) Dark fur keeps bears cool.
Example Output: C

Example Input: Lichens are symbiotic organisms made of green algae and fungi. What do the green algae supply to the fungi in this symbiotic relationship?  
 (A) carbon dioxide (B) food (C) protection (D) water
Example Output: B

Example Input: Atoms of which of these elements are part of many organic molecules?  
 (A) calcium (B) magnesium (C) oxygen (D) silicon
Example Output:
C