Answer: Option D: The amplitude: It is measured by the center line of a wave to the crest or trough.
Explanation:
Using the crest or trough of a single wave, wavelength, frequency, amplitude and energy can be measured.
The energy is measured using the amplitude and frequency of the wave. Hence, option A is incorrect.
The frequency is how fast the crest passes i.e. Number of oscillations per second. It is inversely proportional to the wavelength of the wave which is the distance between two crests or troughs. Hence, both the options B and C are incorrect.
The amplitude is the center line of a wave to the crest or trough. Hence, option D is correct. Amplitude can be measured using the crest or trough of a single wave.