How is the cabin ventilated in the Cessna 172?

The cabin of the Cessna 172 is ventilated primarily through the use of vents and windows. The aircraft is designed with adjustable air vents located in the cabin that allow for the flow of fresh air. Additionally, opening the windows provides natural ventilation, which is especially useful during flight when the aircraft is moving, as this allows for a breeze to flow into the cabin.

This method of ventilation is particularly effective in maintaining comfort for occupants, as it enables pilots and passengers to control the amount of fresh air they receive. The other options, such as air conditioning systems and operating the landing gear, do not apply to the Cessna 172 because this model typically does not have an air conditioning system, and the landing gear does not contribute to cabin ventilation. Engine exhaust is also unrelated, as it does not serve a purpose in providing clean airflow into the cabin. Hence, using vents and windows is the appropriate and practical approach to ventilating the cabin in a Cessna 172.