When using NAT, what can external users see?

When using Network Address Translation (NAT), external users can only see the external NAT address. NAT functions by allowing multiple devices on a private network to share a single public IP address. It translates internal private IP addresses to a public IP address, creating a layer of abstraction and security. As a result, any communication from internal devices to the outside world appears to originate from the public NAT address.

This means external users do not have visibility into the specific internal addresses or configurations of the local area network. They cannot see the details of devices on the private network, nor can they track any dynamic changes to internal IP addresses since NAT always presents a single external address for incoming and outgoing traffic. Thus, the correct option reflects the essential privacy that NAT provides to the internal network.