You work as a network Exchange administrator at Company.com.The Company.com network currently consists of a single Active Directory forest containing a single domain named Company.com.The Company.com organization makes use of Microsoft Exchange Server 2010 as their messaging solution.During the course of the business week you receive instruction from Company.com to install a new Exchange server to the network whilst ensuring that the network users are able to connect from the Internet to the new server using Exchange ActiveSync. What should you do？（）

• A、You should consider having the Anonymous authentication enabled for the Microsoft-Server- ActiveSync virtual directory.
• B、You should consider having the Windows Integrated Authentication enabled for the Microsoft-Server- ActiveSync virtual directory.
• C、You should consider having the internal URL for the Microsoft-Server-ActiveSync virtual directory modified.
• D、You should consider having the external URL for the Microsoft-Server-ActiveSync virtual directory modified.