71. In a gas turbine propulsion installation, the typical control system is designed to perform which of the following three functions?

Gas turbine control systems are designed for operational control, safety control, and monitoring. These functions manage power and speed, prevent unsafe conditions, and provide operational data. Pneumatic, hydraulic, and electric systems are components used to achieve these functions, not primary functions themselves. Speed control and braking are aspects of operational control or shafting systems, respectively, and are not distinct primary functions.