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: Alex looked at an electric toothbrush that had a plug with three metal prongs. Why are these prongs made out of metal?  
 (A) Metal doesn't get hot and melt when you plug it into the outlet. (B) Metal is strong and is less likely to break when you plug it into the outlet. (C) Metal is an insulator and prevents shocks when you plug it into the outlet. (D) Metal is a conductor and completes a circuit when you plug it into the outlet.

A: D
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Q: Bacteria that enter the body are destroyed by which type of cells?  
 (A) white blood cells (B) red blood cells (C) kidney cells (D) lung cells

A:
A
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