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]: What is the function of skin on the human body?  
 (A) Skin has pores that help the body sense odor. (B) Skin protects the body from harmful substances. (C) Skin brings oxygen directly into the body's bloodstream.
[EX A]: B

[EX Q]: One method of heat distribution is a baseboard forced hot water system. A baseboard system carries hot water through a pipe that passes through many small, flat plates called fins. What is the purpose of these fins?  
 (A) to dissipate the heat of the hot water flowing through the pipe (B) to prevent the baseboard from coming in contact with hot surfaces (C) to replace the heated air leaving the system with cold air (D) to prevent dust and other particles from entering the baseboard
[EX A]: A

[EX Q]: To use energy from the Sun to power household appliances, the solar energy must be converted to  
 (A) heat energy. (B) light energy. (C) nuclear energy. (D) electrical energy.
[EX A]:
D