The correct answer is: B. Frequency of waves.
Hertz (Hz) is a unit of frequency in the International System of Units (SI) and is defined as one cycle per second. It is named after Heinrich Hertz, a German physicist who was the first to conclusively prove the existence of electromagnetic waves.
Frequency is the number of waves that pass a given point in a given amount of time. It is measured in cycles per second, or Hertz (Hz). The higher the frequency, the shorter the wavelength.
Wavelength is the distance between two consecutive peaks or troughs of a wave. It
is measured in meters (m). The longer the wavelength, the lower the frequency.Intensity is the amount of energy carried by a wave. It is measured in watts per square meter (W/m2). The higher the intensity, the more energy is carried by the wave.
Clarity is a measure of how well a wave can be seen or heard. It is not a physical quantity and is not measured in any units.