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]: Four students tried to find out which magnet was the strongest. They each shared one idea. Which idea shows scientific thinking?
(A) We can pick the longest magnet. (B) We can pick the heaviest magnet. (C) We can measure the strength of the magnets. (D) We can vote for the magnet that we think is the strongest.
[EX A]: C

[EX Q]: A shallow container of salt water is placed in sunlight for a day. Which is the most likely result?
(A) All of the mixture will evaporate. (B) The salt will keep the water from evaporating. (C) The salt will separate from the water and float at the top of the container. (D) Only the water will evaporate and the salt will remain in the container.
[EX A]: D

[EX Q]: Theresa studied different forms of energy. Which is the best way of expressing the amount of mechanical energy exerted by a force?
(A) kilowatts (B) kilocalories (C) newton-meters (D) foot-pounds per second
[EX A]:
C