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 characteristic of frogs is an adaptation to living in water?  
 (A) strong legs (B) webbed feet (C) dull colors (D) moist skin

A: B
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Q: What is the function of skin on the human body?  
 (A) Skin has pores that help the body sense odor. (B) Skin protects the body from harmful substances. (C) Skin brings oxygen directly into the body's bloodstream.

A: B
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Q: Where does air go when a person breathes in?  
 (A) Into the heart (B) Into the stomach (C) Into the lungs (D) Into the liver

A:
C
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