TASK DEFINITION: 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.
PROBLEM: Which of the following happens in our solar system?  
 (A) Earth revolves around the sun once per day. (B) The moon revolves around Earth once per day. (C) Earth revolves around the sun once per year. (D) The moon revolves around Earth once per year.

SOLUTION: C

PROBLEM: A star is a large astronomical body that  
 (A) reflects light. (B) condenses light. (C) emits light. (D) absorbs light.

SOLUTION: C

PROBLEM: Which of these are broken down during chemical, but not physical, changes?  
 (A) elements (B) mixtures (C) solutions (D) compounds

SOLUTION:
D