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 set contains kingdoms that contain only heterotrophs?   
 (A) Protists, Fungi (B) Bacteria, Animals (C) Plants, Fungi (D) Animals, Fungi

A: D
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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: Students studying the atmosphere want to display the percentage of each greenhouse gas as compared to the total amount of greenhouse gases found in the atmosphere. Which representation would be most appropriate for displaying these percentages?  
 (A) bar graph (B) line graph (C) pie chart (D) data table

A:
C
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