Answer: The correct statement is A is the wavelength; B is the crest; C is the trough
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Explanation:
Crest is defined as the point on a wave which have the the maximum value of upward displacement. This corresponds to letter B in the image.
Trough is defined as the opposite of crest which is the minimum or lowest point in a wave. This corresponds to letter C in the image.
Wavelength is defined as the distance between two successive troughs or crests. This corresponds to letter A in the image.
Hence, the correct statement is A is the wavelength; B is the crest; C is the trough
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