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 Q]: Which of these elements is found in the greatest amount in organisms?  
 (A) carbon (B) iron (C) lead (D) neon
[EX A]: A

[EX Q]: A car runs out of fuel while traveling on a level road and eventually comes to a stop. Which of the following best explains why the car stops?  
 (A) Some of the energy of the car was lost to friction. (B) Some of the energy of the car was destroyed. (C) The amount of kinetic energy increased. (D) The amount of useful energy increased.
[EX A]: A

[EX Q]: Sodium chloride (NaCl) is formed in a chemical reaction between sodium (Na) and chlorine (Cl_{2}). What is sodium chloride?  
 (A) an element (B) a mixture (C) a compound (D) an atom
[EX A]:
C