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.

Input: Consider Input: Solar radiation provides more heat near the equator than near the poles on Earth. The greatest amount of heat is moved away from the equator by  
 (A) ocean currents. (B) aquatic plants. (C) surface winds. (D) tectonic plates.

Output: A


Input: Consider Input: A student hypothesizes that algae are producers. Which question will best help the student determine if this is correct?  
 (A) Do algae consume other organisms? (B) Which organisms consume algae? (C) Do algae use sunlight to make food? (D) Could an ecosystem survive without algae?

Output: C


Input: Consider Input: What is responsible for changing the remains of prehistoric sea animals into natural gas?  
 (A) time (B) water (C) gravity (D) pressure


Output: D