What is the minimum time the wing anti-ice system must remain on after activation?

The correct answer is based on the operational procedures outlined for the Dassault Falcon 7X regarding the use of the wing anti-ice system. The minimum time that the wing anti-ice system must remain on after activation is set at 5 minutes. This requirement ensures proper functioning of the anti-ice system, allowing it sufficient time to effectively heat the wing surfaces and prevent ice formation.

Keeping the system activated for at least 5 minutes helps ensure that any ice that may have already formed has a chance to melt away, thus maintaining optimal aerodynamic performance. This procedure is critical not only for safe flight operations but also for the overall performance of the aircraft in icing conditions. While options reflecting shorter or longer durations may seem feasible, the specified 5-minute timeframe is validated by engineering assessments and safety protocols put in place for the Falcon 7X, making it the correct choice.