Correct Answer - A
The endoskeleton of mammals have two major divisions: (i) Axis skeleton that lies along the logitudinal axis of the body . It support and protects the organs of the head , neck and trunk. It includes skull, ribs, sternum and vertebal column. (ii) Appendicular skeleton, which os associated with the appendages. it consists of two girdles. the pectoral and girdles the limb bones.