Answer:
It is not true that S waves change the volume of material by compression and expansion.
Step-by-step explanation:
S-waves are transverse seismic space waves (waves moving through the interior of the Earth). With S waves, particles vibrate in the material through which the wave moves (the medium) perpendicular to the way of movement of the wave. Shift occurs in the material, from which it can be deduced that S-waves can only move through elastic materials. S-waves therefore do not occur in liquids or gases.