You are given a science question (hard-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.
--------
Question: How many basic units of information in a DNA molecule are required to encode a single amino acid?  
 (A) 1 (B) 2 (C) 3 (D) 4

Answer: C


Question: As a car burns fuel, a transformation from chemical to mechanical energy takes place. What is the most likely result of the fuel burning?  
 (A) The matter that makes up the car increases. (B) The amount of useful energy decreases. (C) The efficiency of the car increases. (D) The amount of heat energy decreases.

Answer: B


Question: Heat, light, and sound are all different forms of ___.  
 (A) fuel (B) energy (C) matter (D) electricity

Answer:
B