Which of the following bones is part of the axial skeleton?

The sternum is indeed a component of the axial skeleton, which consists of the bones that form the long axis of the body. This includes the skull, vertebral column, and rib cage, all of which support the trunk and protect vital organs. The sternum, commonly known as the breastbone, is located in the center of the chest and serves as an attachment point for ribs and the clavicle, playing an essential role in the structure of the thoracic cavity.

In contrast, the other bones listed—humerus, femur, and tibia—are part of the appendicular skeleton, which includes the limbs and the girdles that attach them to the axial skeleton. The humerus is found in the upper limb, the femur in the thigh of the lower limb, and the tibia in the lower leg. These bones primarily facilitate movement rather than contributing to the body's central framework. Understanding the distinction between axial and appendicular skeletons is crucial for identifying bone functions and locations within the human body.