A server is sending 404 responses to requests from users. Which of the following would MOST likely be a possible cause?

A 404 "Not Found" HTTP status code means the server cannot find the requested resource. If a web server's content (e.g., website files) is stored on an NFS (Network File System) share and that connection is lost, the server will be unable to retrieve the requested files, leading to 404 errors for clients.

If a DNS server is down, users would typically experience connection errors or timeouts because the hostname could not be resolved, not a 404 from the server itself.

A firewall blocking subnets would prevent connection to the server entirely, resulting in connection timeouts or refused connections, not a 404 response from the server.

A denial of service (DoS) attack would typically result in slow responses, timeouts, or server unresponsiveness, not specific 404 error codes from the application.