Which phenomenon cannot be exhibited by Longitudinal Waves?

Hint:The polarization is observed only in the transverse waves. The direction of motion in transverse waves is perpendicular to the direction of oscillation. In the longitudinal waves, the displacement of the particles in the oscillation is along the direction of propagation.

Complete step-by-step solution:
Longitudinal waves cannot be polarized because the transverse wave can vibrate in all directions and is perpendicular to the direction of propagation. So, it is feasible for a transverse wave to continue the vibration in a single plane.
The particles are displaced parallel to the direction of propagation of the waves. A wave vibrating in more than one plane is called an unpolarized wave. Transforming an unpolarized wave into a polarized wave is known as Polarization.
The oscillations' direction can be parallel or perpendicular to the propagation of the wave direction. The oscillation can be specified by polarization waves. The particles are vibrated in the same directions that the wave travels of longitudinal waves. Transverse waves emerge from the polarizer vibrating in the plane. Longitudinal waves vibrate along a single line.
So, the longitudinal waves are the sound waves that do not exhibit polarization.

Note:The longitudinal waves are the displacement of the medium that is parallel to the propagation of the wave.
The particles are vibrated in the same direction that the waves travel in longitudinal waves.
The longitudinal waves transfer their energy by moving their neighbors in the same direction that the energy moves.