Final answer:
A business can place a server outside of its own private network in a DMZ (Demilitarized Zone). A DMZ is used to add an additional layer of security, allowing external access to certain services while protecting the rest of the network.
Step-by-step explanation:
Where can a business place a server outside of its own private network? Among the options provided, a DMZ (Demilitarized Zone) is the correct answer. A DMZ is a physical or logical subnetwork that contains and exposes an organization's external-facing services to an untrusted network, usually the internet.
The primary purpose of a DMZ is to add an additional layer of security to an organization's local area network (LAN); an external attacker only has access to equipment in the DMZ, rather than any other part of the network.
The other options listed, such as NAT (Network Address Translation), LAN (Local Area Network), and TUN (Tunnel), are not places where you can put a server outside of a private network. NAT is a method used to remap one IP address space into another by modifying network address information in the IP header of packets while they are in transit across a traffic routing device.
LAN is a computer network that interconnects computers within a limited area such as a residence, school, laboratory, or office building. TUN refers to network TUNnel, which is a protocol that can encapsulate IP packets over a simulated network device; it is not a place to host servers.