Answer: The correct option is (C).
Step-by-step explanation:
When the particles of the medium travel parallel to the direction of the propagation of the wave then the wave is said to be longitudinal wave.
It needs medium to travel. It can travel in solid, liquid and gas.
The example of the longitudinal wave is a sound wave. Sound wave consists of compression and rarefaction.
When the particles of the medium travel perpendicular to the direction of the propagation of the wave then the wave is said to be transverse wave.
Therefore, the best statement which describes the longitudinal wave is option (C).