Explanation:
You can disable any archival destination as long as you have enough enabled archival destinations left to meet the LOG_ARCHIVE_MIN_SUCCESS threshold value.
Incorrect Answers:
1: You can disable not only optional archival destinations, but mandatory one too.
2: You can disable archival destinations by setting LOG_ARCHIVE_DEST_STATE_n to DEFER.
3: You can disable all mandatory archival destinations without any restrictions.
Oracle 8, DBA Certification Exam Guide, Jason S. Couchman, p. 577-585
Chapter 12: Overview of Backup and Recovery

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