One Characteristic of the Class Holothuroidea Is That They

One characteristic of the class Holothuroidea is that they:

A) are predators that consume partially digested prey.
B) are mostly extinct species.
C) have a reduced endoskeleton consisting of microscopic plates embedded in the body wall.
D) have movable spines that are used to facilitate locomotion.
E) have a distinct central disk with very long, slender arms.