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: Organisms contribute to the water cycle mainly through the process of  
 (A) irrigation. (B) evaporation. (C) precipitation. (D) transpiration.

A: D
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Q: Bones support the body. What pulls and pushes on bones to move them?  
 (A) blood (B) nerves (C) muscles (D) skin

A: C
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Q: Which of these things will dissolve in water?  
 (A) iron filings (B) wood chips (C) sand (D) sugar

A:
D
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