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: What is the function of the nucleus in a cell?  
 (A) provides energy (B) provides nutrients (C) controls activity (D) controls movement

A: C
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Q: When a tree suffers from a decreased ability to transport materials within the phloem, what is directly impacted?  
 (A) volume of water in the xylem (B) flow of necessary nutrients (C) response to environmental factors (D) rate of photosynthesis in leaves

A: B
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Q: Which human activity would have the greatest positive impact on the water quality of a stream?  
 (A) releasing warm water into the stream (B) driving cars through the stream (C) reducing use of fertilizers near the stream (D) increasing use of chemicals near the stream

A:
C
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