Answer:
C) Amplitude.
Explanation:
By definition, the amplitude of wave is defined as the distance from the rest position to the highest or lowest point of the wave.
The highest and lowest points of the wave are called crests and troughs respectively; Therefore, the amplitude of the waves is also said to be the height of the wave from its rest position to its crest—and also the height of the from the rest position it its trough.
This means Choice C (amplitude) is the correct term used to describe the height of a wave from its rest position to its crest.
P.S: Choice A, the crest height, can also be the correct term, but the term ''amplitude'' is often used and is more technical.
