Your network contains five Active Directory forests.
You plan to protect the resources in one of the forests by using Active Directory Rights Management Services (AD RMS)
Users in all of the forests will access the protected resources.
You need to identify the minimum number of AD RMS clusters required for the planned deployment.
What should you identify?

A.
One root cluster and five licensing clusters

B.
One licensing cluster and five root clusters

C.
Five root clusters

D.
Five licensing clusters

Explanation:
C is Correct.
Root Cluster – this is the first server in an AD RMS cluster, which automatically becomes the Root Cluster by default. The Root Cluster handles all certification and
licensing requests for the domain in which it is installed. It is recommended to have as few AD RMS Clusters as possible.
Each Forest will become a Root Cluster.
Licensing-Only Cluster – Licensing-Only Clusters perform only licensing (not certification). Licensing only clusters decrease performance as they have to constantly
“check back” with the Root Cluster for licensing integrity. Licensing clusters are ONLY recommended when you have a department that requires a different licensing
arrangement to your other departments.
In the case of this question: We have 5 Forest, so we have to have at least 5 Root Clusters. We have no need for licensing clusters.
https://technet.microsoft.com/en-us/library/cc771175.aspx
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