You have an Exchange Server 2010 organization. You have a group named Help Desk that contains all the help desk users in the organization. You need to ensure that the Help Desk group can manage all the mailboxes and mail-enabled contacts in the organization. The solution must minimize the number of permissions assigned to the Help Desk group. Which management role should you assign to the Help Desk group？（）

A. Mail Recipients
B. Mail Recipient Creation
C. Organization Client Access
D. Recipient Policie