How does ATC utilize radar for traffic management?

ATC utilizes radar primarily for monitoring aircraft positions and ensuring proper separation between them. This function is crucial for maintaining safety in the skies. Radar allows air traffic controllers to visualize the real-time location of aircraft within their controlled airspace, providing them with accurate and timely information about each aircraft's altitude, speed, and trajectory. By using this data, controllers can effectively manage traffic flows, direct aircraft to maintain safe distances from each other, and facilitate smooth arrivals and departures, minimizing the risk of mid-air collisions.

Other options, while related to aviation, do not align with the primary roles of radar in air traffic control. Recording flight plans is generally done through flight data systems, not radar, which focuses on live tracking. Providing pilot weather updates may involve radar data but is not the main purpose of radar; rather, it could be facilitated through other communication systems. Lastly, assisting in in-flight entertainment is entirely outside the realm of air traffic control duties; radar is not involved in this aspect of airline operations at all. Therefore, the correct answer emphasizes the central role of radar in maintaining safety and efficiency in air traffic management.