Your Company upgrades its network to 100 Mbps. You remove the old network adapter and install a new 10/100 Mbps network adapter into a Windows 2000 Professional computer. You configure the TCP/IP protocol settings to be the same as they were for the previously installed network adapter.   When you restart eh computer, however, you cannot access the network. You try to ping your network adapter’s TCP/IP address locally. You receive the following error message. “Request timed out.” Next, you try to ping 127.0.0.1 and receive the same error message.   What must you do?（）

• A、Configure a different TCP/IP address
• B、Enable DHCP in the TCP/IP properties
• C、Enable DNS in the TCP/IP properties
• D、Configure the network adapter to run at 100 Mbps only
• E、Replace the network adapter.