What key aspect does terminal radar separation focus on for safety?

Answer: C — Distance between aircraft

Terminal radar separation primarily emphasizes maintaining a safe distance between aircraft. This is crucial for ensuring that aircraft do not come too close to one another during approach, departure, and while in the terminal airspace. By monitoring and enforcing specific separation minima, air traffic controllers can reduce the risk of mid-air collisions and ensure a safe environment for aircraft operating in close proximity. While time of flight, aircraft speed, and altitude differences are all relevant factors in overall air traffic management and can influence separation techniques, they are not the primary focus of terminal radar separation. The core principle is ensuring adequate horizontal and vertical separation between aircraft to maintain safety and operational efficiency in busy airspace.