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 tool would be best to use for counting the number of legs on an ant?  
 (A) ruler (B) hand lens (C) calculator (D) microscope

A: B
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Q: Many things can contribute to the development of a theory. A student made a list of some things that might help scientists develop a theory. Observations Calculations Conversations Publications From the student's list, which must be used in the development of every theory?  
 (A) Observations (B) Conversations (C) Publications and calculations (D) Calculations and conversations

A: A
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Q: Which of the following is a way that everyone can help with conservation efforts?  
 (A) camp in the woods (B) use biodegradable materials (C) visit a landfill (D) use disposable plates

A:
B
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