Which system does the CTO utilize to make travel reservations?

The Global Distribution System (GDS) is the correct answer because it is a centralized network that enables travel agents and officials to book travel reservations, including flights, hotels, and car rentals. The Chief Travel Officer (CTO) leverages the GDS to access a comprehensive inventory of travel options and facilitate bookings efficiently. This system integrates various data from airlines, hotels, and other travel-related services, allowing for streamlined processes in making travel arrangements. It is widely used across the travel industry, which makes it the preferred tool for managing travel reservations in a systematic manner.

Other systems mentioned, such as the Defense Finance and Accounting Service and the Government Travel Card system, serve specific functions related to payment and financial management rather than booking travel directly, while the Government Reservation System is often focused more on official travel protocols rather than the broader range of travel services offered by a GDS.