Which command can be used to check the reachability of the default gateway from a workstation?

The command that is used to check the reachability of the default gateway from a workstation is "ping." When you use the ping command, it sends Internet Control Message Protocol (ICMP) echo request packets to the specified IP address—in this case, the IP address of the default gateway. If the default gateway is reachable, it responds with echo reply packets, indicating that communication is possible.

This command is fundamental in network troubleshooting, allowing users to verify connectivity to other network devices, including routers and gateways. By successfully receiving replies from the default gateway, you can confirm that the local workstation is correctly configured for IP networking and that the gateway is operational.

The other options serve different purposes: "tracert" is used to trace the route packets take to reach a destination, "ipconfig" displays the current IP configuration of the machine but does not test reachability, and "netstat" provides network statistics and active connections but does not check reachability directly. Thus, using ping is the most appropriate method for this specific task.