You are given a science question (hard-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: Leucine is one of the amino acids your body needs but cannot make. Which of these happens so that the human body can obtain leucine?  
 (A) The body converts other amino acids to leucine. (B) The body stores carbohydrates containing leucine. (C) The body breaks down fatty acids to obtain leucine. (D) The body digests protein in food to obtain leucine.

A: D
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Q: Because water can hold a large amount of heat, which effect do oceans have on nearby land areas?  
 (A) They prevent rapid extreme temperature changes. (B) They form high-pressure areas that cause magma currents. (C) They provide the energy that triggers volcanic events. (D) They lower the freezing point of fresh water.

A: A
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Q: A person catches and measures a large fish called a halibut. She thinks that this halibut is above average in size. To help support her thinking, it would be most helpful to measure  
 (A) many types of fish. (B) many fish of the same type. (C) fish from the same location. (D) fish during a different season.

A:
B
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