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: The burning of fossil fuels affects the atmosphere by  
 (A) adding more heat and carbon dioxide. (B) reducing the amount of necessary heat. (C) taking water vapor out of the atmosphere. (D) putting more oxygen in the atmosphere.

A: A
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Q: The greatest amount of diversity can be found among which type of organism?  
 (A) plants (B) animals (C) bacteria (D) fungi

A: C
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Q: What should students use to identify the percent chance of a trait being passed down from a parent to its offspring?  
 (A) a graph (B) a flow chart (C) a data table (D) a Punnett square

A:
D
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