What Happens Inside a Rock as a Wave Front from an S

What happens inside a rock as a wave front from an S wave passes through?

A) The little parcel of rock rotates about its own location in an ellipse until the wave passes.
B) The little parcel of rock shimmies from side to side as the wave passes, with the greatest motion at the Earth's surface, dying out with depth.
C) The volume of the rock stays fixed, but it shears back and forth, distorting the rock's internal shape as the wave passes through.
D) The rock moves toward and away from the earthquake as the volume of the material alternately expands and contracts, changing the rock's density while the compression-rarefaction wave passes through.