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: In one area, a large source of prey for eagles is rabbits. If the number of rabbits suddenly decreases, what effect will it most likely have on the eagles?  
 (A) Their numbers will increase. (B) Their numbers will decrease. (C) They will adapt new behaviors. (D) They will migrate to new locations.

A: B
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Q: How does sedimentary rock form?  
 (A) sediments cool (B) sediments melt (C) sediments separate (D) sediments compress

A: D
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Q: Scientists think that the rise in global temperature during the last one hundred years is due to an increase of carbon dioxide in the atmosphere. Which question would best help scientists assess the claim that humans are responsible for the rising global temperature?  
 (A) What is the mechanism by which carbon dioxide heats Earth? (B) What is the source of most of the carbon dioxide in the atmosphere? (C) What is the source of the increase of carbon dioxide in the atmosphere? (D) What is the increase in the concentration of carbon dioxide in the atmosphere?

A:
C
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