Which system is typically associated with monitoring the aircraft's performance and ensuring safety?

The flight management system is crucial for monitoring the aircraft's performance and ensuring safety during all phases of flight. It integrates various functions such as navigation, performance calculations, and guidance to optimize the flight path. This system continuously evaluates data from multiple sensors and systems onboard, enabling pilots to make informed decisions that enhance safety and operational efficiency. It assists in managing the aircraft's trajectory, ensuring compliance with air traffic control, and optimizing fuel usage, all critical for safe flight operations.

While the other systems play important roles within the aircraft—such as managing fuel efficiency, controlling environmental conditions for passenger comfort, or overseeing propeller performance—they do not primarily focus on the comprehensive oversight of the aircraft's overall performance during flight. This distinction makes the flight management system the most appropriate choice for the question regarding monitoring performance and ensuring safety.