A longitudinal wave is a wave transversing along the length of a longitudinal wave, the motion of the disturbance is parallel to the wave motion.
What is a longitudinal wave?
A longitudinal wave is a wave that is transversing along the length. When the displacement of medium and travel of wave is same in that condition wave is known as the longitudinal wave.
It requires some medium to travel. A mechanical and sound wave is an example of a longitudinal wave.
Hence the right option is parallel.
To learn more about the longitudinal wave refer to the link;
https://brainly.com/question/8497711?referrer=searchResults
