changes in which property are heard when the doppler effect occurs?\no pitch\no amplitude\no volume\no…

Brief Explanations:

The Doppler effect for sound is perceived as a change in pitch. Pitch is related to the frequency of the sound wave. When there is relative motion between the source of the sound and the observer, the frequency (and thus pitch) changes. Amplitude is related to loudness, volume is a subjective measure of loudness, and while wavelength also changes in the Doppler - effect, what is heard is the change in pitch.

Answer:

pitch