Which part of the body is included in the axial skeleton?

The correct answer is the skull and vertebral column, as these structures are essential components of the axial skeleton. The axial skeleton primarily serves to support the head and body and protect the brain, spinal cord, and thoracic organs. It is composed of the skull, which encases the brain, and the vertebral column, which provides stability and protection for the spinal cord.

In contrast, the other choices consist of bones that do not belong to the axial skeleton. For example, the humerus and femur are part of the appendicular skeleton, which includes limbs and their attachments to the axial skeleton. The pelvis and scapula are also part of the appendicular skeleton, serving as attachments for the lower and upper limbs, respectively. The clavicle and ribs, while related to the collarbone and thorax, comprise part of the connections between the axial and appendicular skeleton, but are not classified solely within the axial skeleton framework. Thus, the skull and vertebral column are distinctly recognized as integral to the structure and function of the axial skeleton.