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: The engineering team that is designing a scientific research station on the Arctic permafrost has to provide the station with energy for cooking, heating, and lighting. Considering the fragile environment and other conditions there, the best choice is probably to  
 (A) build a wind turbine. (B) have fuel trucked in. (C) have a pipeline built. (D) build a solar collector.
Example Output: A

Example Input: Which of the following is the most likely cause of earthquakes?  
 (A) shifting rock layers (B) crashing meteorites (C) rotation of the core (D) magnetic force
Example Output: A

Example Input: Which of the following has the greatest direct influence on movement of the lithosphere?  
 (A) the Sun (B) the Moon (C) Earth's core (D) Earth's mantle
Example Output:
D