Answer:
The correct answer is a rarefaction.
Explanation:
Sound waves are longitudinal waves that propagate in a medium, such as air. As the vibration continues, a series of successive condensations and rarefactions form and propagate from it. The pattern created in the air is something like a sinusoidal curve to represent a sound wave.
There are peaks in the sine wave at the points where the sound wave has condensations and valleys where it has rarefactions.
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