What is the primary purpose of the Air Traffic Control (ATC) system within the National Airspace System (NAS)?

Why: Remote Pilot Study Guide (p. 12): "The primary purpose of the ATC system is to prevent a collision between aircraft operating in the system and to organize and expedite the flow of traffic."

• Confuses ATC's operational safety role with the FAA's separate aircraft-registration function, handled through FAADroneZone rather than air traffic control.
• Confuses ATC with the FAA's separate airman-certification function; ATC manages traffic flow and separation, it does not issue remote pilot certificates.