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: A hearing aid is a small device that contains an amplifier, a battery, a microphone, and a speaker. Which part of a hearing aid functions to detect sounds in the user's environment?  
 (A) the amplifier (B) the battery (C) the microphone (D) the speaker

A: C
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Q: Water at 20°C in an uncovered pan is evaporating very slowly. What could be done to the water to make it evaporate more quickly?  
 (A) Cover it. (B) Heat it. (C) Place it in the dark. (D) Put salt in it.

A: B
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Q: A group of workers needs to move a piano from the second floor of a building. The piano is too wide to fit through the door, so they will lower the piano to the ground through a window. Which tool would be best to help the workers lower the piano from the window?  
 (A) wheel and axle (B) inclined plane (C) pulley (D) wedge

A:
C
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