Answer:C)Crest
Explanation:In wave terminologies:
Crest: The highest point of a wave above the equilibrium or baseline level.
Trough: The lowest point of a wave below the equilibrium or baseline level.
Peak: This term can sometimes be used interchangeably with crest, but crest is more commonly used to specifically denote the highest point.
Amplitude: The maximum extent of a vibration or oscillation, measured from the position of equilibrium. It represents the height of the wave from the baseline to the crest (or depth to the trough).
Therefore, option C) Crest is the correct answer.