The distance between two successive troughs or crests is known as the wavelength There are 3 complete wavelengths are shown in this image.
What is wavelength?
The distance between two successive troughs or crests is known as the wavelength. The peak of the wave is the highest point, while the trough is the lowest.
The wavelength is also defined as the distance between two locations in a wave that have the same oscillation phase.
The length of a wave is measured in its propagation direction. The wavelength is measured in meters, centimeters, nanometres, and other units since it is a distance measurement.
Hence Option D is correct. There are 3 complete wavelengths are shown in this image.
To learn more about the wavelength refer to the link;
brainly.com/question/7143261
