A. Membrane that surrounds the lungs B. Partition that divides the abdominal and thoracic cavities C. Partition that divides the nostrils D. Membrane that lines the chest cavity
The diaphragm is a muscle that separates the thoracic and abdominal cavities, crucial for breathing.
Explanation:
The diaphragm is a dome-shaped muscle that separates the thoracic cavity from the abdominal cavity. It plays a vital role in breathing by contracting and expanding, allowing air to enter and exit the lungs.
