You have a VPN server that runs Windows Server 2003 Service Pack 2 (SP2). The VPN server supports only PPTP connections. A firewall protects the VPN server from the Internet. From a remote computer connected to the Internet, you attempt to connect to the VPN server. During the connection attempt, you receive a message that your user name and password are being verified. You then receive the following error message: “Error 721: The remote computer is not responding.”You need to ensure that you can establish a VPN connection to the VPN server from the Internet. What should you do?()
A. On the VPN server, enable LAN routing.
B. On the VPN server, create a demand-dial interface.
C. On the firewall, allow inbound connections that use TCP port 1701.
D. On the firewall, allow inbound connections that use Generic Route Encapsulation (GRE) protocol 47.