Final answer:
The correct answer to the question is c) Manubrium. The three parts of the sternum are the manubrium, body, and xiphoid process, with the manubrium being the upper section.
Step-by-step explanation:
The upper section of the sternum is known as the manubrium. The sternum consists of three main parts: the manubrium, body, and xiphoid process. The manubrium is the wider, superior portion, the middle section is called the body, and the lower small cartilaginous structure that becomes ossified over time is the xiphoid process. The jugular notch is the shallow, U-shaped upper border of the manubrium.
The sternoclavicular joint is where the clavicle meets the manubrium at its lateral margins, and the angle of Louis, also known as the sternal angle, is located at the junction between the manubrium and the body of the sternum. Therefore, the correct answer to the question is c) Manubrium.