What comprises the axial skeleton?

• A. Torso, head, limbs
• B. Shoulders and hips
• C. Pelvis and femur
• D. Skull, vertebral column, and rib cage

Answer: (D)

The axial skeleton forms the body's central axis, protecting the brain, spinal cord, and thoracic organs, and providing the framework for the head, neck, and trunk. It includes the skull, vertebral column, and rib cage.

That’s why listing the skull, vertebral column, and rib cage is the best choice. The other options point to parts of the appendicular skeleton—the limbs and the girdles (shoulder and pelvic)—which are responsible for movement and attachment of the limbs, not the central axis. In short, the axial skeleton=central axis; the appendicular skeleton=limbs and girdles.