An administrator wants to identify the process identifier (PID) associated with active connections and listening ports, while keeping addresses numeric. Which command is the best choice?

### Why this is right `-a` includes connections and listening ports, `-n` displays numeric addresses and port numbers, and `-o` includes the owning process identifier. Together, these options match the requested view. ### The concept `netstat` reports network state on the local computer. Its switches select which parts of that state appear. Numeric output avoids resolving addresses and ports into names, which can make results quicker to display and easier to compare exactly. The process identifier helps an administrator investigate which running process owns a connection, but it does not establish that the process is safe or unsafe. The other options provide routing, statistics, or Ethernet information rather than the requested connection-to-process view. ### The other options - **`netstat -r`**: displays the routing table, which describes routes rather than associating active connections with process identifiers. - **`netstat -s -p tcp`**: displays Transmission Control Protocol (TCP) statistics, not the requested list of connections with process identifiers. - **`netstat -e`**: displays Ethernet statistics, not connection ownership. ### Terms - **PID**: Process Identifier. A number that identifies a running process. - **TCP**: Transmission Control Protocol. A transport protocol that provides ordered, reliable delivery of data. - **Routing table**: A set of rules used to decide where network packets should be forwarded. - **Ethernet**: A family of wired local network technologies. - **Listening port**: A port waiting for incoming network connections. ### Remember For numeric connection details with owning process identifiers, use `netstat -ano`.