Final answer:
The ribs and sternum form a protective shield around the internal organs, particularly the heart and lungs, which are located in the thoracic cavity. option d is correct.
Step-by-step explanation:
The ribs and sternum form a protective shield around the internal organs. Specifically, the rib cage or thoracic cage, which includes the ribs, sternum, and thoracic vertebrae, protects the organs in the thoracic cavity, mainly the heart and lungs. These structures are crucial for the body's survival, and the bones of the rib cage provide a hard exterior to shield these organs from potential injury. While the skull protects the brain and the vertebral column safeguards the spinal cord, it is the rib cage that ensures the safety of the thoracic cavity's vital organs.
The ribs and sternum form a protective shield around the **internal organs.** Specifically, they protect vital organs in the thoracic cavity, including the heart and lungs. This bony structure, known as the ribcage, provides a crucial layer of protection against external forces and injuries.
The ribcage's design, along with the sternum, offers structural support and safeguards these vital internal organs, ensuring their protection while allowing for essential physiological functions such as respiration and circulation. This protective shield plays a critical role in maintaining the integrity and functionality of the internal organs within the thoracic cavity.