How is expedited deplaning executed?

Expedited deplaning is a procedure that allows for the swift and efficient evacuation of passengers from an aircraft, particularly during emergencies. In this context, choosing the option where all passengers exit through the main cabin door (MCD) is correct because it streamlines the process, reduces confusion, and ensures that passengers can quickly leave the aircraft in a controlled manner.

Using a singular exit point like the MCD facilitates the orderly flow of passengers, minimizing the risk of bottlenecks that could occur if multiple exits are used. In emergencies, every second counts, so having a single, clear exit prevents delays and enhances safety.

The other options do not align with the standard procedures for expedited deplaning. Allowing passengers to retrieve personal belongings would unnecessarily prolong the evacuation process, which is not ideal during emergencies. Exiting only the flight crew first could also hinder the process, as passengers need to be evacuated as quickly as possible. Activating emergency lights is a precautionary measure that may assist during an evacuation, but it does not represent a method of executing expedited deplaning. Thus, the approach of having all passengers exit through the MCD is the most efficient and safe method for this scenario.