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: How do most fish get the oxygen they need to survive?  
 (A) They take in water and break it down into hydrogen and oxygen. (B) Using their gills, they take in oxygen that is dissolved in water. (C) They get their oxygen from the food they eat. (D) They come to the surface every few minutes to breathe air into their lungs.

A: B
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Q: Overuse of soil for farming causes local disruptions of several Earth subsystems. Which of these is a part of the biogeochemical cycle that experiences the most severe local disruption?  
 (A) release of carbon into the atmosphere (B) release of oxygen into the atmosphere (C) cycling phosphorus into the soil (D) cycling hydrogen into the soil

A: C
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Q: Which stimulus causes a porcupine to extend its quills?  
 (A) lunar effect on Earth (B) seasonal temperature changes (C) threatening behavior by predators (D) environmental encroachment by humans

A:
C
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