Explanation:
It’s possible to add a new master to a replication group without quiescing the group without impacting end users who are executing data manipulation language (DML) commands on the replicated tables.
Incorrect Answers:
1: The new master site already may not have existing replication groups to achieve this result.
2: You cannot add a new master to a replication group without quiescing the group by issuing a single command to create, populate, and activate the new master.
3: When the master definition site is not the same for all of the master groups you cannot add a new master to a replication group without quiescing the group.
Reference:
OCP Oracle9i Database: New Features for Administrators, Daniel Benjamin, p. 83-93
Chapter 2: Availability Enhancements
Oracle 9i New Features, Robert Freeman, p. 146-147
Chapter 5: Miscellaneous Oracle9i Features and Enhancements

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