Ventilation in the body means process of?

The correct answer is gaseous exchange.

Ventilation is the process of moving air into and out of the lungs, which facilitates the exchange of gases between the body and the environment. During inhalation, oxygen-rich air enters the lungs, and during exhalation, carbon dioxide-rich air is expelled. This process is essential for maintaining adequate levels of oxygen in the blood and removing waste products like carbon dioxide.