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: Earth is composed of layers of material with different properties. Which of the following is most likely to be in constant motion?
(A) core (B) mantle (C) oceanic crust (D) continental crust

A: B
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Q: In the morning, students observed puddles of water all over the playground. What would best explain why the playground was dry in the afternoon?
(A) Animals drank the water. (B) The wind stopped blowing. (C) Someone dried the puddles. (D) The water evaporated during the day.

A: D
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Q: Some antibiotics used to treat infections in humans are also used to treat chickens, but some groups oppose this practice. The overuse of the antibiotics will most likely influence the natural selection of which type of organisms?
(A) chickens that naturally make the antibiotics (B) microbes that are resistant to the antibiotics (C) microbes that are susceptible to the antibiotics (D) chickens that are resistant to infection

A:
B
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