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.

Q: Which of the following is the best example of potential energy?  
 (A) a fallen rock (B) a burning match (C) a liter of gasoline (D) a red-hot piece of iron

A: C
****
Q: A movie studio will use two methods of communication, television and the Internet, to advertise a new movie. Which of the following must both methods of communication use in order to show the advertisements to viewers around the world?  
 (A) systems to locate viewers (B) networks to transmit signals (C) printing to create the images (D) software to search for images

A: B
****
Q: A cell releases energy from storage molecules on the inner surface of the membrane that surrounds the cell. The location of these molecules best indicates that the cell  
 (A) is part of a multicellular organism. (B) is prokaryotic. (C) performs sexual reproduction. (D) is eukaryotic.

A:
B
****