Which correctly identifies the parts of a wave in this diagram?

question options:

a is the trough; b is the wavelength; c is the crest

a is the wavelength; b is the crest; c is the trough

a is the trough; b is the crest; c is the wavelength

a is the crest; b is the trough; c is the wavelength

, I've seen these type of questions before.  They're horrible xd

So what you need to know is that what Crest, Trough, and the wavelength is. 

The Crest is the very top of the wave so it would be B

The Trough of the wave is the very bottom, so the answer to that would be C

and the wavelength of the wave is basically how long/far the wave spreads.  So that would be A. 

To solve this, simply analyze the graph provided and find specific details of the wave such as wavelength, trough, crust, etc.  

So the correct answer would be: B, "A is the wavelength; B is the crest; C is the trough" 

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