Under which circumstance should you retain a VFR aircraft on frequency?

Retaining a VFR aircraft on frequency is beneficial when there can be an operational advantage, and proper coordination has been established. This situation allows for better communication and support to the aircraft, ensuring that air traffic control can provide assistance with traffic advisories, navigation, or any changes in flight plans that may be beneficial to the pilot.

While a VFR aircraft might be retained solely for the area of responsibility, that does not inherently provide the operational benefit that is desired. Similarly, a pilot's request to stay on frequency is important, but it must be weighed against the context of operational needs and coordination. Retaining an aircraft during emergencies is also critical, but the approach should generally prioritize operational efficiency and safety for all traffic involved, making the need for coordination key in this decision-making process. Ultimately, Option B integrates essential aspects of air traffic control management, focusing on operational benefit and collaboration.