The correct answer is A. amplitude.
Amplitude is the height of a wave, measured from its midline to its peak. It is a measure of the wave’s energy. The amplitude of a wave does not affect its velocity, wavelength, or frequency.
Velocity is the speed at which a wave travels. It is determined by the wave’s frequency and wavelength. The higher the frequency, the higher the velocity. The longer the wavelength, the lower the velocity.
Wavelength is the distance between two consecutive crests or troughs of a wave. It is a measure of the size of a wave. The wavelength of a wave does not affect its amplitude, velocity, or frequency.
Frequency is the number of waves that pass a given point in a given amount of time. It is measured in hertz (Hz). The higher the frequency, the more waves pass a given point in a given amount of time. The lower the frequency, the fewer waves pass a given point in a given amount of time.
In conclusion, the amplitude of a wave is independent of its velocity, wavelength, and frequency.