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: The molecule ATP is composed of elements commonly found in organic molecules. Which of the following is one of these elements?  
 (A) aluminum (B) calcium (C) phosphorus (D) tin

SOLUTION: C

PROBLEM: Different units of measurement are more useful in some settings than in others. Which unit of measurement is most used when comparing distances within the solar system?  
 (A) the mile (B) the kilometer (C) the light year (D) the astronomical unit

SOLUTION: D

PROBLEM: Jagged mountains would most likely become rounded hills through which process?  
 (A) erosion (B) deposition (C) volcanic activity (D) chemical change

SOLUTION:
A