Explanation:
Resetting redo logs for the primary database will invalidate the standby database, it needs to be recreated from the primary database again.
Incorrect Answers:
2: The standby database cannot be used in any mode, it needs to be rebuild again.
3: A new standby database incarnation will not automatically be started because of invalidation of standby database.
4: The redo log of the standby database will not be reset automatically, no new archive logs can be applied to the standby database because of reset logs in the primary database.
Oracle 8, DBA Certification Exam Guide, Jason S. Couchman, p. 1159
Chapter 24: Oracle8i New Features Topics

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