Which of the following is part of the appendicular skeleton?

The appendicular skeleton is primarily involved in movement and comprises the bones of the limbs and the girdles that attach them to the trunk. The shoulder girdle, which includes the clavicles and scapulae, plays a crucial role in connecting the arms to the body and facilitating a wide range of motion at the shoulders. This makes it an essential component of the appendicular skeleton.

In contrast, the skull is part of the axial skeleton, which protects the brain and supports the structures of the face. The rib cage, while vital for protecting the organs within the thoracic cavity, is also considered part of the axial skeleton, along with the vertebral column, which encompasses the spine and supports the head, protects the spinal cord, and serves as an attachment point for ribs and muscles. Hence, the shoulder girdle is the correct choice as it directly pertains to the appendicular skeleton.