You have an Exchange Server 2010 organization. You create a distribution group for all users in your company.

You need to ensure that new users can add their mailboxes to the distribution group.

What should you do?

A.
Modify the group scope of the distribution group.

B.
Modify the approval mode of the distribution group.

C.
Modify the security settings of the distribution group.

D.
Modify the authentication settings of the ECP virtual directory.