Final answer:
The Central Software Server (CSS) is the subsystem in the Standard Terminal Automation Replacement System Operational Site that retains and distributes software for a site.
Step-by-step explanation:
The subsystem in the Standard Terminal Automation Replacement System Operational Site (SOS) that has a server retaining and distributing software for a site is the Central Software Server (CSS). The CSS is responsible for managing and distributing the system software updates and configurations to various components within the SOS infrastructure. It acts as a central repository for the software, ensuring that all elements of the system are consistently updated and maintained with the latest software revisions.
The Standard Terminal Automation Replacement System (STARS) is a computer system used in air traffic control that provides automated support for control room functions. Within the STARS Operational Site (SOS) subsystem, the Central Software Server retains and distributes software for a site. It is responsible for storing and maintaining the software used by the air traffic controllers at a specific location, ensuring that the correct versions are available and accessible.