Answer: C- Remote desktop uses port 3389 by default, so you should determine whether the firewall has blocked it.
Key Takeaway: While RDP TCP port 3389 provides an easy way to connect remotely to corporate resources, it is notorious for many security vulnerabilities, including ransomware. That said, when several protocols are used on a network, and a firewall is used, make sure that the necessary ports are left open on the firewall. You can do this using the firewall’s control panel. You can refer to the RFC documentation for the default ports used by the network protocols.
