You need to design the Exchange 2003 server configuration for remote e-mail access. What should you do？（）

• A、Configure the front-end servers in each branch office to be members of a new Active Directory site
• B、Configure the back-end servers to have server encryption certificates issued by a commercial certification authority （CA）
• C、Configure two back-end servers to be members of a Network Load Balancing cluster. Configure Network Load Balancing for inbound RPC connections
• D、Configure multiple front-end servers in each branch office to be members of a Network Load Balancing cluster. Configure Network Load Balancing for inbound HTTPS connections