Which of the following is defined as the expulsion of air from the lungs?

The term that defines the expulsion of air from the lungs is expiration. During this process, the diaphragm and other muscles relax, allowing the lungs to recoil and push air out. This action is essential for removing carbon dioxide from the body, which is a byproduct of metabolism.

In contrast, inspiration refers to the act of drawing air into the lungs, while ventilation encompasses the overall process of both inhalation and exhalation of air. Respiration involves the exchange of gases, which includes the uptake of oxygen and the release of carbon dioxide, but it is a broader term that describes the overall physiological process rather than the specific act of expelling air. Understanding these terms helps clarify the mechanics of breathing and the respiratory system's role in maintaining homeostasis in the body.