A penetration tester is hired to do a risk assessment of a company's DMZ. The rules of engagement states that the penetration test be done from an external IP address with no prior knowledge of the…

A white box test grants the tester full knowledge of internal systems, network diagrams, and source code, which is the opposite of the described conditions.

A grey box test provides partial knowledge of the internal environment (such as user-level credentials or limited documentation), which was not given to this tester.

Red box is not a recognized standard penetration testing methodology type - it is not a valid classification in this context.

A black box test is performed from the perspective of an external attacker who has no prior knowledge of the internal systems, network topology, or source code. The tester starts only with publicly available information and an external IP, exactly as described in the rules of engagement. This approach most closely replicates a real-world external attack scenario against the DMZ.