Final answer:
The netstat utility utilizes the -o switch to display the process ID alongside active TCP connections, aiding in the identification of network-communicating processes.
Step-by-step explanation:
The switch used with the Windows netstat utility to show the process ID is -o. The netstat command is a powerful tool that can provide various types of information about the network connections on a system.
When you run netstat with the -o switch, it displays active TCP connections and includes the process ID (PID) for each connection. This can be particularly useful when trying to identify which processes are communicating over the network.