Which aviation system uses algorithms to prevent mid-air collisions?

The correct option is TCAS, which stands for Traffic Alert and Collision Avoidance System. This system is specifically designed to reduce the risk of mid-air collisions by using onboard aircraft data and air traffic information to track the positions and movements of other aircraft in close proximity.

TCAS employs algorithms that analyze the flight paths of nearby aircraft and determine if they are on a collision course. If a potential conflict is detected, TCAS issues alerts to the flight crew, providing timely advisories for preventive action. These alerts include "Traffic" advisories that indicate the presence of nearby aircraft and "Resolution" advisories that suggest climbing or descending maneuvers to ensure safe separation from the other aircraft.

In contrast, the other systems listed have different roles within aviation. FAA Flight Service provides pilots with important pre-flight and in-flight information, such as weather briefings and route planning, rather than collision avoidance. The Ground Control Station is primarily involved in remotely controlling unmanned aerial vehicles (UAVs) and does not focus on mid-air collision avoidance. The Flight Management System is chiefly responsible for flight planning and navigation, helping pilots manage the aircraft’s route and performance but does not directly engage in preventing mid-air collisions like TCAS does.