American Academy of Professional Coders (AAPC) Practice Exam 2026 - Free AAPC Practice Questions and Exam Prep Guide

The appendicular skeleton is primarily composed of the bones that enable movement and provide support in the appendages of the body. This includes not only the arm bones but also the leg bones, as well as the shoulder (pectoral) and pelvic (hip) girdles, which connect the limbs to the axial skeleton. The shoulder girdle allows for a wide range of motion in the arms, while the pelvic girdle supports the weight of the upper body when sitting and standing, as well as providing stability for walking and running.

In contrast, the other options focus on more limited components. For instance, mentioning only the arm or leg bones does not encompass the full scope of the appendicular skeleton. Similarly, including the vertebrae and skull elements pertains to the axial skeleton rather than the appendicular one, as the axial skeleton primarily comprises the skull, vertebral column, and rib cage. Therefore, the presence of the shoulder and pelvic girdles is essential in defining the skeletal components of the appendicular skeleton.