Under what circumstance may authorized couriers open a parcel containing classified material for inspection at border crossings?

Authorized couriers may open a parcel containing classified material for inspection at border crossings when ordered by Customs, Immigration, or Police officials. This is because security protocols allow for law enforcement agencies to conduct necessary inspections to ensure compliance with legal requirements and to maintain national security.

In the context of border crossing, law enforcement has the authority to inspect packages regardless of their contents. Couriers must comply with these requests while also following established procedures to safeguard the classified information they are transporting. This balances the needs for security and the legal duties of law enforcement.

The other options do not reflect the proper protocols in scenarios involving inspections of classified materials. For instance, requests from a courier's supervisor are not sufficient to override security protocols. Routine checks by the Department of Defense rarely involve the opening of classified materials unless specifically authorized. Additionally, opening a parcel in the presence of a security detail is not a recognized condition allowing for the inspection of classified items unless ordered by an appropriate authority. Thus, the correct answer centers on compliance with orders from Customs, Immigration, or Police officials.