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]: Wave energy from the ocean can be harnessed to power generators to make electricity. Energy from ocean tides can also be used to make electricity. How would you categorize these two sources of energy?  
 (A) Both are renewable. (B) Both are nonrenewable. (C) Wave energy is nonrenewable. Tidal energy is renewable. (D) Wave energy is renewable. Tidal energy is nonrenewable.
[EX A]: A

[EX Q]: Which is the most important safety measure to follow when using an acid in a classroom laboratory?  
 (A) wearing protective clothing and goggles (B) keeping the window open (C) closing the door to the hall (D) using bright fluorescent lights
[EX A]: A

[EX Q]: What are the two main jobs of the skeletal system?  
 (A) support and protect the body (B) digest food and carry messages for the body (C) get rid of wastes and defend the body from disease (D) sense changes in the environment and carry food through the body
[EX A]:
A