Earthworms Use Their Hydrostatic Skeletons to Move Through the Soil

Earthworms use their hydrostatic skeletons to move through the soil.As earthworms move through the soil they

A) contract their circular muscles,which press their longitudinal muscles,which in turn stretch to elongate the segments of their bodies.
B) contract their longitudinal muscles,which press their circular muscles,which in turn stretch to elongate the segments of their bodies.
C) contract their circular muscles,which stretch their longitudinal muscles,which in turn stretch to enlarge the segments of their bodies.
D) contract their circular muscles,which press their clitellum and attached setae into the burrow;with the setae as anchors,the earthworms are able to pull their bodies through the soil.
E) contract their longitudinal muscles,which compress their circular muscles,which in turn reduce each segment's circumference allowing forward movement.