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: Which difference between water and ice results in ice floating on cold water?  
 (A) heat (B) shape (C) density (D) volume

A: C
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Q: Which type of air mass forms over the ocean near the equator?  
 (A) moist and warm (B) moist and cool (C) dry and warm (D) dry and cool

A: A
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Q: Selective breeding has resulted in plants that are resistant to pests and produce a higher yield of fruits and vegetables. Which of these is the most likely disadvantage that can result from this process?  
 (A) decreased genetic diversity (B) habitat destruction (C) overpopulation (D) increased erosion

A:
A
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