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: Historically, how has the compass been used?  
 (A) for navigation (B) to predict weather (C) to measure temperature (D) for mineral identification
Example Output: A

Example Input: Which of these will most likely result from small meteoroids entering the atmosphere of Earth?  
 (A) a decrease in air temperature (B) the appearance of shooting stars (C) an decrease in atmospheric ozone (D) the appearance of the Northern Lights
Example Output: B

Example Input: Which statement best explains why ice cubes will melt in a glass of tea?  
 (A) The tea becomes saturated. (B) The ice cubes gain energy. (C) The tea's freezing point increases. (D) The ice cube's melting point decreases.
Example Output:
B