You have a hosted Exchange organization. All servers in the organization have Exchange Server 2010 SP1 installed.

You need to group a set of users for administrative delegation.

What should you create?

A.
A new distribution group.

B.
A new management role.

C.
A managed folder mailbox policy.

D.
A new role assignment policy.

Explanation:
When you change role assignments, the changes you make will probably be between role groups and role assignment policies. By adding, removing, or modifying role assignments to or from these role assignees, you can control what permissions are given to your administrators and users, in effect turning on and off management of related features.

Regular role assignments enable the role assignee to access the management role entries made available by the associated management role. If multiple management roles are assigned to a role assignee, the management role entries from each management role are aggregated and applied. This means that if a role assignee is assigned the Transport Rules and Journaling roles, the roles are combined, and all the associated management role entries are given to the role assignee. If the role assignee is a role group or role assignment policy, the permissions provided by the roles are then given to the users assigned to the role group or role assignment policy.

The management role assignment policy is a special object in Exchange 2010. Users are associated with the role assignment policy when their mailboxes are created or if you change the role assignment policy on a mailbox. This is also what you assign end-user management roles to. The combination of all the roles on a role assignment policy defines everything that the user can manage on his or her mailbox or distribution groups.

Reference:

http://technet.microsoft.com/en-us/library/dd638100.aspx
http://technet.microsoft.com/en-us/library/dd335131.aspx