Which of the following IP addresses must use NAT to access resources on the internet?

• A. 10.5.4.2
• B. 172.16.52.4
• C. 192.168.1.4
• D. All of the above

Answer: (D)

Private IP addresses, such as those listed in the options, are defined by specific ranges that cannot be routed on the public internet. These ranges include:

• The 10.0.0.0 to 10.255.255.255 range

• The 172.16.0.0 to 172.31.255.255 range

• The 192.168.0.0 to 192.168.255.255 range

Since all the provided IP addresses—10.5.4.2, 172.16.52.4, and 192.168.1.4—fall within these private ranges, they must utilize Network Address Translation (NAT) to communicate with devices on the internet. NAT serves as a bridge between private networks and the internet by translating the private IP addresses to a public IP address that is routable.

This functionality enables multiple devices within a private network to access the internet using a single public IP address. Each device's private IP address is mapped to the public address through NAT, allowing responses to return to the correct private device. Thus, all of the listed addresses require NAT to facilitate access to the internet.