Which of the following is NOT a part of the GPS system?

The GPS system is composed of three primary components: the space segment, the control segment, and the user segment.

The space segment consists of the satellites that broadcast signals, which provide the essential data for determining precise positioning. The control segment includes the ground stations that monitor and manage the GPS satellites, ensuring their accurate operation and maintenance. The user segment is made up of the devices and systems that receive GPS signals and interpret the data for practical use in navigation, mapping, and other applications.

The concept of a "drone segment" does not fit into the established architecture of the GPS system, as it is not an official component recognized in the training and operation of GPS. While drones can utilize GPS technology for navigation and control, they do not constitute a separate segment of the GPS itself. Thus, identifying "C" aligns with comprehending the established components of the GPS framework.