问题：

[单选] You have a server that runs Windows Server 2003 Service Pack 2 (SP2). The server is configured as a network address translation (NAT) router. The server has two network adapters and provides Internet access for the network.You need to prevent traffic on port 21 from being sent to the Internet. All other outbound traffic must be allowed.What should you do?（） 

A . On the network adapter that is connected to the LAN, enable TCP/IP filtering. 
B . On the network adapter that is connected to the Internet, enable TCP/IP filtering. 
C . From the Routing and Remote Access snap-in, open the properties of the interface connected to the Internet, select the Services and Ports tab, and define a new service. 
D . From the Routing and Remote Access snap-in, open the properties of the interface connected to the Internet, select the NAT/Basic Firewall tab, and define a new static packet filter.