Which of the following bones is NOT part of the appendicular skeleton?

The correct answer indicates that the skull is not part of the appendicular skeleton. The appendicular skeleton comprises the bones of the limbs and the girdles that connect them to the axial skeleton, which includes the skull, vertebral column, and rib cage. Specifically, the appendicular skeleton includes the bones of the arms (like the radius), legs (such as the femur), and the connectors like the clavicle, which links the arm to the thorax.

In contrast, the skull is categorized under the axial skeleton, which serves as the central structure of the body, providing support and protection for the brain and the organs of the head. Thus, understanding the differentiation between the axial and appendicular skeletons is key for recognizing which bones belong to each category.