Final answer:
The correct answer is a) Concave, Sternum. The sternum exhibits a concave shape at its lateral margins where it joins with the clavicles, forming the sternoclavicular joint.
Step-by-step explanation:
The bony thorax, also known as the thoracic cage, includes the sternum, ribs, and thoracic vertebrae. It provides protection for the thoracic cavity organs, such as the heart and lungs, and serves as a support structure for the upper body. Considering the anatomy of the thoracic cage, we can determine the correct answer to the question: The bony thorax is typically concave at the lateral margins of the sternum.
The sternum is a flat bone located at the anterior of the chest and consists of the manubrium, body, and xiphoid process. The ribs are curved bones that attach to the thoracic vertebrae and to the sternum via costal cartilages. The lateral margins of the manubrium, where the clavicles join the sternum at the sternoclavicular joint, are mildly concave in shape.