What is the transaction code used to inquire the lost gun file in NCIC?

The transaction code used to inquire about the lost gun file in NCIC is QG. This code specifically allows law enforcement officers to access information pertaining to firearms that have been reported lost or stolen. By using the QG code, officers can obtain crucial data that helps them track and recover illicitly obtained firearms, thereby enhancing public safety and ensuring compliance with firearms regulations.

It is important to recognize that each of the other codes listed corresponds to different inquiries or transactions within the NCIC system. Therefore, understanding that QG is explicitly designated for lost gun inquiries clarifies why it is the correct choice in this context.