What does the appendicular skeleton include?

The appendicular skeleton includes the bones that form the limbs and the girdles that attach them to the axial skeleton. Specifically, this encompasses the shoulder girdle (consisting of the clavicle and scapula) and the pelvic girdle (comprising the hip bones), as well as all the bones of the arms, legs, hands, and feet.

This classification is vital for understanding human anatomy, as the appendicular skeleton is responsible for facilitating movement and supporting the attachment of limbs. Other options do not accurately represent the full scope of the appendicular skeleton. For instance, while the ribs and sternum are part of the thoracic cage, they are components of the axial skeleton, not the appendicular. Similarly, the vertebral column and skull are entirely part of the axial skeleton, as their roles are primarily protective and supportive for the central nervous system and organs. Lastly, limiting the appendicular skeleton to just the leg and arm bones fails to account for the girdles and other associated bones, which are also crucial for proper limb function and mobility.