Answer:
C. Air particles vibrate, but they do not travel with the sound.
Step-by-step explanation:
Sound wave is a longitudinal wave in which medium particles moves to and fro parallel in the direction of energy propagation of propagation of sound.
So here when sound energy travels into the medium the particles start vibrating in the medium such that the vibration is parallel to the energy propagation.
While energy is propagating through the medium the net displacement of medium particles is zero which means the medium particles do not travel along with the propagation of sound.
so here correct answer would be
C. Air particles vibrate, but they do not travel with the sound.