Which cavity contains the heart and lungs?

The thoracic cavity is the correct answer because it is specifically designed to house vital organs essential for respiration and circulation, namely the heart and lungs. This cavity is located in the upper part of the trunk and is bounded by the rib cage, the diaphragm, and the mediastinum.

Within the thoracic cavity, the lungs are protected by the rib cage and are involved in the gas exchange process, while the heart, which is centrally located, is responsible for pumping blood throughout the body. The structure of the thoracic cavity is crucial for the functioning of both these organs, as it provides a supportive environment that facilitates breathing and circulation.

In contrast, the abdominal cavity primarily contains digestive organs and structures, the pelvic cavity hosts reproductive and some excretory organs, and the spinal cavity encases the spinal cord. None of these cavities contain the heart and lungs, which are specifically situated within the thoracic cavity.