Step 1: Definition of WAN.
A Wide Area Network (WAN) is a network spanning a substantial geographical region, encompassing areas like cities, countries, or the entire globe.
Step 2: Analysis of Options.
- Option (1) PAN: A Personal Area Network (PAN) is a localized network, typically confined to a small space such as a room or personal office. - Option (2) WWW: The World Wide Web (WWW) is a collection of interlinked hypertext documents, but it is not a network itself. - Option (3) Ethernet: Ethernet is a protocol utilized for Local Area Networks (LANs), not for WANs. - Option (4) Internet: The Internet represents the largest WAN, connecting billions of devices worldwide.
Step 3: Determination.
The appropriate answer is the Internet, given its status as the largest WAN connecting devices globally.
Final Answer: \[\boxed{\text{The Internet is the largest WAN.}}\]