What does the pectoral girdle consist of?

The pectoral girdle, also known as the shoulder girdle, is an anatomical structure that connects the upper limbs to the axial skeleton. It consists specifically of the clavicle (collarbone) and the scapula (shoulder blade).

The clavicle serves as a strut that helps stabilize the shoulder by connecting the arm to the trunk, while the scapula provides a surface for muscle attachment and enables a wide range of shoulder movements. Together, these two bones form a pivotal area that allows for the mobility and flexibility necessary for upper limb function, such as reaching and lifting.

In contrast, the other options include bones that belong to different body regions or functions. Ribs and sternum are part of the thoracic cage, femur and tibia are bones of the lower limb, and humerus and radius are part of the forearm and upper limb respectively. None of these combinations relate to the structure or function of the pectoral girdle.