You suspect that a gateway machine on your network has failed but you are unsure which machine. Which command will help locate the problem?

`ps` lists running processes on the local machine and has no visibility into network topology or remote gateway status.

`netstat` displays local socket connections and routing table entries but cannot probe the status of remote gateways along a path.

`nslookup` performs DNS name resolution and is unrelated to diagnosing gateway reachability or path failures.

`ifconfig` shows local network interface configuration and statistics but cannot detect failures on remote gateway devices.

`traceroute` sends probe packets with incrementing TTL values and records each intermediate router (gateway) that responds, along with latency. If a gateway has failed, `traceroute` will show packets stopping or timing out at the hop corresponding to that machine, directly pinpointing the failure point on the network path.