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 Server 2010 environment. TestKing.com contains 30 offices that consist of 1，500 users. AT present TestKing.com users make use of Microsoft Exchange Server to access their e-mail messages. During the course of day you receive an instruction from the CIO to ensure that users in their offices is only able download the list of recipients for their offiche as well asensuring that they are able to communicate to any other user in the orgranization via e-mail. What should you do？（）

A. The best option is to set up 30 new managed folder mailbox policies and 20 e-mail address policies.
B. The best option is to set up 30 new mailbox database and then move the mailboxes from each officheto a separate mailbox database.
C. The best option is to set up 30 new address lists and 30 offline address books （OABs）
D. The best option is to set up 30 new dynamicdistribuition groups and then create 20 new global address lists （GALs）.