What ventilation system uses ducts and a central exhaust fan to expel stale air from a building?

The correct answer identifies the system primarily focused on the movement of air within a building, specifically designed to expel stale air and introduce fresh air. A ventilation system is responsible for controlling air quality by removing contaminants and ensuring a consistent exchange of indoor and outdoor air.

This type of system often utilizes ducts to distribute and exhaust air effectively, which is crucial in maintaining a healthy indoor environment. The inclusion of a central exhaust fan helps to actively pull stale air out of the building, ensuring that fresh air can replace it.

While air conditioning and heating systems also involve air movement, their primary functions are to cool and heat air respectively, rather than ventilate. Forced air systems can include heating and air conditioning components but do not specifically denote a system designed solely for ventilation purposes. Therefore, ventilation is the term that most accurately describes the mechanism of using ducts and a central fan to expel stale air.