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: A meteoroid becomes a meteorite when it  
 (A) impacts the surface of a planet. (B) encounters the atmosphere of a planet. (C) makes a complete orbit around a planet. (D) starts to burn up in the atmosphere of a planet.

A: A
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Q: The excessive use of nitrogen-based fertilizers causes runoff that increases the nitrogen content of lakes and bays. These nitrogen compounds directly affect the aquatic ecosystems by  
 (A) interfering with the water cycle. (B) decreasing the predator population. (C) increasing the rate of algae growth. (D) causing aquatic animals to grow larger.

A: C
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Q: As members of a food web, humans are considered to be  
 (A) producers. (B) consumers. (C) decomposers. (D) scavengers.

A:
B
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