What is the inferior portion of the sternum commonly referred to as?

The correct choice refers to the xiphoid process, which is indeed the inferior portion of the sternum. This small, sword-shaped structure is located at the lower end of the sternum, where it serves as an important attachment point for various muscles, including the diaphragm. Additionally, the xiphoid process can be a point of reference during CPR when locating the correct position for chest compressions.

The other terms correspond to different parts of the sternum. The manubrium is the upper part of the sternum that connects with the clavicles and the first pair of ribs. The costal cartilage refers to the cartilage that connects the ribs to the sternum, providing flexibility and support to the rib cage. The body of the sternum, positioned between the manubrium and the xiphoid process, forms the central part of the sternum that articulates with the true ribs. Each of these components has a distinct anatomical role, highlighting the importance of understanding their specific names and locations in the human body.