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 a common use of the mineral graphite?  
 (A) to make glass (B) as a source of iron (C) to make pencil leads (D) as a household cleaner

A: C
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Q: A student counts ants in an ant colony every day at the same time. The student writes the date of observation in one column in a notebook and the number of ants counted on each date in a second column. Which best describes how the student arranged the information?  
 (A) pie chart (B) data table (C) bar graph (D) scatterplot

A: B
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Q: Air is composed of nitrogen, oxygen, and other gases. Based on that information, air can be described as  
 (A) a compound. (B) an element. (C) a mixture. (D) a molecule.

A:
C
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