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.

Ex Input:
The moon goes through phases as it revolves around Earth. During which phase of the moon would it be possible for a solar eclipse to occur?  
 (A) new moon (B) full moon (C) waning (D) waxing

Ex Output:
A


Ex Input:
A boy pulls a sweater off over his head. His hair is attracted to the sweater due to  
 (A) a magnetic force (B) a heat transfer (C) a chemical change (D) an electrical charge

Ex Output:
D


Ex Input:
What object is made of hot gas and is the most massive object in our solar system?  
 (A) the Sun (B) an asteroid (C) a comet (D) a terrestrial planet

Ex Output:

A