You work as the enterprise exchange administrator at TestKing.com. TestKing.com makes use of Microsoft Exchange Server messaging solution. The TestKing.com network consists of a single ActiveDirectory domain named testking.com. TestKing.com is configured to run in an Exchange 2010 environment. A new TestKing.com security policyrequires that only approved mobile devices can connect via the Exchange ActiveSync.  You have receivedinstructions from the CIO to stop specified mobile devices to connect to the Exchange servers. What should you do？（）

• A、The best option is to create a new Exchange ActiveSync device access role.
• B、The best option is to create a new Exchange ActiveSync policy.
• C、The best option is to create a new client throttling policy.
• D、The best option is to create a new Microsoft Server ActiveSync virtual directory.