What is the cause of this issue?

A company has removed the VDC from the replication group and is no longer able to add it back.

What is the cause of this issue?
A . The same cannot be added back to the replication group; it must be given another name
B . The VDC cannot be added back to the existing replication group: a new replication group must be created for the VDC
C . The same VDC can be added back to the replication group; but only before failover processing is completed successfully
D . Removing the VDC from the replication group initiates failover processing for permanent failures

Answer: A