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: The fusion reaction that fuels the Sun converts hydrogen into
(A) carbon. (B) iron. (C) neon. (D) helium.

A: D
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Q: Which of these will most likely result from small meteoroids entering the atmosphere of Earth?
(A) a decrease in air temperature (B) the appearance of shooting stars (C) an decrease in atmospheric ozone (D) the appearance of the Northern Lights

A: B
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Q: The living systems of plants and animals are constantly taking in water to continue the processes of life. What eventually happens to most of that water?
(A) It is converted into hydrogen and oxygen. (B) It is returned to the environment. (C) It is broken down by bacterial decay. (D) It is permanently combined with other compounds.

A:
B
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