Which of the following are types of precision approaches?

Precision approaches are designed to provide accurate vertical and horizontal guidance to pilots for landing, ensuring higher safety and efficiency, especially in low visibility conditions. The correct answer identifies three methods that fit this category: ILS (Instrument Landing System), GLS (Ground-Based Augmented System), and PAR (Precision Approach Radar).

ILS is the most widely used precision approach method, providing both lateral and vertical guidance through a combination of radio signals and approach lighting. GLS is a more advanced system that uses satellite technology and is still in development at various locations, offering precision similar to ILS but with the advantage of GPS technology over ground-based systems. PAR is a radar-based precision approach providing real-time guidance to pilots by using radar to determine the aircraft's position relative to the runway.

The other choices mention systems suitable for various navigation but do not all provide precision approach capabilities. For example, while NDB (Non-Directional Beacon) and VOR (VHF Omnidirectional Range) are widely used for navigation, they do not provide the same level of precise guidance required for a precision approach. Thus, the identified methods in the correct answer are the established forms of precision approaches used in modern aviation.