How can a flight attendant reset the lavatory call button?

The lavatory call button system is designed to alert the flight attendants when a passenger needs assistance in the lavatory. To reset this system, the flight attendant can utilize the call cancel button located on the FA panel. When a passenger presses the call button in the lavatory, it activates an alert both in that specific lavatory and on the FA panel, indicating that assistance is required. By pressing the call cancel button on the FA panel, the flight attendant acknowledges the call and resets the system, effectively silencing the alert and marking the passenger's request for assistance as addressed.

The other options would not effectively reset the lavatory call system. For instance, while pressing a call cancel button at a passenger seat may affect an individual seat’s call system, it does not interact with the lavatory alert. Similarly, turning off the cabin lights or simply clearing the lavatory area does not have any direct impact on resetting the call alert system in operation. Thus, the FA panel’s call cancel button is the correct and designated method for flight attendants to reset the lavatory call indication.