You need to prepare the Exchange organization for the deployment of Exchange Server 2010 Mailbox, Client Access, and Hub Transport servers

You have an Exchange organization that contains Exchange Server 2003 Service Pack 2
(SP2) servers. All servers are members of one Administrative Group and one Routing
Group.
You plan to transition the organization to a hosted Exchange Server 2010 environment.
You need to prepare the Exchange organization for the deployment of Exchange Server
2010 Mailbox, Client Access, and Hub Transport servers.
What should you do first?

A.
Disable all link state updates.

B.
Create a Routing Group connector.

C.
Modify the Active Directory schema.

D.
Delete all Recipient Update Service (RUS) objects.