D is the correct answer.
In the badly drawn diagram attached, you will find the <em>yellow</em> represents wavelength, which is the distance between identical points on consecutive waves.
The <em>green</em> represents the amplitude, which is the distance between the origin (middle) and crest/trough (top/bottom)
Black, it will slowly maje it darker
Answer: sure i would love to help i love dance but now that i am not going to school i have spare time just need to contact me!
Explanation: