Which HTTP status code corresponds to SIP "404"?

The correct answer is the HTTP status code that corresponds exactly to SIP "404," which indicates that the requested resource could not be found. In the context of both SIP (Session Initiation Protocol) and HTTP (Hypertext Transfer Protocol), the "404 Not Found" status signifies that the server did not locate the requested resource at the given location. This indicates a failure in finding a destination for the SIP request, just as it does in the context of web requests.

Understanding the correspondence between SIP and HTTP status codes is important for anyone working in VoIP or related fields, as it helps integrate and manage communications and web services effectively. The other options do not represent the same meaning as SIP "404." For instance, "401 Unauthorized" implies a need for credentials, "200 OK" indicates successful requests, and "500 Internal Server Error" refers to a server malfunction. Each of these codes serves a distinct purpose in communicating the status of a request, making "404 Not Found" the only appropriate match for SIP "404."