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: Which of the following would be more likely to pollute a river?  
 (A) allowing beavers to build a dam (B) spreading fertilizer near the river (C) mowing the grass on the river bank (D) fishing from a bridge over the river

A: B
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Q: The energy that is stored in food originally comes from  
 (A) air (B) soil (C) sunlight (D) water

A: C
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Q: How long does it take light from the nearest star other than the Sun to reach Earth?  
 (A) Less than 1 second (B) About 1 hour (C) About 1 month (D) About 4 years

A:
D
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