What is a key configuration requirement for Hybrid Message Service High Availability deployment with multiple IM and Presence clusters?

What is a key configuration requirement for Hybrid Message Service High Availability deployment with multiple IM and Presence clusters?
A . You must have the Intercluster Sync Agent working across your IM and Presence clusters.
B . You must have the Intercluster Lookup Service working across all of your IM and Presence clusters.
C . Your IM and Presence Service clusters must have Multiple Device Messaging disabled.
D . AXL service should be activated only on the publisher of each IM and Presence cluster.

View Answer

Answer: A