When defining SmartDirectory for High Availability (HA), which of the following should you do?

A.
Replicate the same information on multiple Active Directory servers.

B.
Configure Secure Internal Communications with each server and fetch branches from each.

C.
Configure a SmartDirectory Cluster object.

D.
Configure the SmartDirectory as a single object using the LDAP cluster IP. Actual HA functionality is configured on the servers.