Answer:
Longitudinal Waves
Step-by-step explanation:
As we know that longitudinal waves are those in which medium molecules oscillates parallel to the direction of propagation of wave or propagation of energy.
So here we know that when wave is sent into the medium then the energy will travels from left to right and also the propagation is given from left to right also.
So here we will say that the wave here must be longitudinal wave.
While if the medium particles will oscillates perpendicular to the propagation of energy or propagation of waves, then it is known as transverse type of wave.
So here correct answer will be
LONGITUDINAL WAVE