Which Statement About the Endoskeletons of Vertebrates Is True

Multiple Choice

Which statement about the endoskeletons of vertebrates is true?

A) The muscles are attached to a nonliving support structure.
B) The rib bones are part of the appendicular skeleton.
C) They allow the animal to expand without molting.
D) They consist of bone, only.
E) Only one bone is required to form a joint.