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 radio station broadcasting across a large area is experiencing thunderstorms. How will the radio waves from the station be affected?  
 (A) wavelength will be increased (B) amplitude will be unchanged (C) frequency will be distorted (D) speed will be decreased

A: C
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Q: Marta studied different forms of energy. Which two types of energy travel in waves?  
 (A) light and sound (B) electrical and sound (C) chemical and light (D) chemical and electrical

A: A
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Q: Which would be the best conductor of electricity?  
 (A) air (B) cork (C) water (D) silver

A:
D
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