If the particles of the medium vibrate perpendicular to the wave's propagation, the wave is known as:

A wave motion is a type of disturbance that travels through a medium as a result of repeated vibrations of the medium's particles about their mean positions.

Longitudinal wave motion is the wave motion in which individual particles of a medium execute simple harmonic motion about their mean position along the same direction as the wave. 

Vibration of particles in a medium and wave propagation are perpendicular to each other in transverse wave motion.

Particles of the medium vibrate perpendicular to the wave's propagation direction in transverse waves. As a result, option 4 is correct.