What function does the stall warning system serve?

The stall warning system in an aircraft is designed specifically to alert the pilot of an impending stall condition. A stall occurs when the aircraft exceeds its critical angle of attack, leading to a loss of lift. The stall warning system typically utilizes a horn or light to provide an audible or visual indication to the pilot, allowing them to take appropriate corrective actions before the stall occurs. It plays a critical role in enhancing flight safety by giving pilots advance notice of the possibility of a stall, so they can respond by reducing the angle of attack or other necessary actions to maintain control of the aircraft.

The other options listed relate to different systems and functionalities within the aircraft, such as engine performance monitoring, fuel management, and cabin environment control, which do not relate to the stall warning system's primary purpose.