What is included in the axial skeleton?

The axial skeleton primarily consists of the central core of the human body, which includes the skull, thorax (rib cage), vertebral column (spine), and the hyoid bone. This structure serves essential functions, such as protecting vital organs, providing support for the body, and allowing for the attachment of muscles that are involved in movement and respiration.

The skull houses and protects the brain, while the thorax encases the heart and lungs. The vertebrae provide support and flexibility to the spine, and the hyoid bone plays a crucial role in tongue movement and swallowing. Understanding the components of the axial skeleton is significant in various fields, including anatomy, health care, and physical therapy, as it forms the framework for the body's posture and alignment.

The other choices contain bones associated with the appendicular skeleton, which includes the limbs and their attachments—arms and legs, hands and feet bones, and the pelvis and shoulder girdle. Therefore, the correct response accurately identifies the parts of the human skeleton that fall under the classification of the axial skeleton.