How will the Flight Deck door be secured once the weight and balance paperwork has been reviewed?

Once the weight and balance paperwork has been reviewed, the flight deck door will be secured by being closed and locked. This procedure is vital for maintaining security in the flight deck and ensuring that only authorized personnel have access to that area of the aircraft during flight operations. Properly securing the flight deck is a crucial part of aviation safety protocols, especially in relation to hijacking and unauthorized access.

In this context, having the door closed and locked helps protect the flight crew from potential threats and ensures that they can perform their duties with minimal distraction and risk. The other options do not conform to safety regulations; for instance, keeping the door open or unlocked would compromise security and violate standard operating procedures. Thus, the requirement to have the flight deck door closed and locked after reviewing weight and balance paperwork reinforces the importance of security in aviation operations.