Answer:
D. Amplitude
Step-by-step explanation:
The amplitude of sound waves determines how loud or soft a sound is. The loudness of a sound is a function of its amplitude.
Amplitude is defined as the maximum displacement of wave from its source.
The amplitude of a sound wave determines how loud the sound can be heard.
A wave with a large amplitude will have a large loudness. Waves of low amplitude will also show softness.
Amplitude is one of the fascinating properties of waves.