Your network contains an internal network and a perimeter network. You have one Exchange Server 2010 server on the internal network. You install Windows Server 2008 R2 on a new server in the perimeter network. You need to ensure that you can install the Edge Transport server role on the new server.  What should you do（）？ 

• A、Join the new server to an Active Directory domain.
• B、Install Active？Directory Lightweight Directory Services on the new server.
• C、Run ImportEdgeConfig.ps1 on the existing Exchange Server 2010 server.
• D、Open TCP port 88 and TCP port 3268 on the firewall between the perimeter network and the internal network.