A network engineer must determine which ports are currently established from a client device.

The correct choice is D. netstat because the display shown is a classic list of active TCP sessions, including the protocol , local address , remote address , and the connection state such as ESTABLISHED and TIME_WAIT . That is exactly the kind of information a technician checks when trying to see what connections a workstation currently has open.

The distractors do different jobs. nslookup and dig are DNS utilities. They help query name resolution records, but they do not list active client sessions. nmap is mainly used to scan hosts and ports across the network, usually to discover services or assess exposure on target systems. It does not normally produce a local session table in this format.

For Network+ purposes, this falls under troubleshooting with command-line tools. When the goal is to inspect current sessions on the local device and confirm whether a port is open, listening, or already connected, netstat is the expected command. The wording “currently established from a client device” is the clue that matters most. The question is not asking what ports exist on a remote server; it is asking what active connections are present on the machine itself. That makes netstat the best fit.