Explanation:
In NOARCHIVELOG mode only offline (closed) database backups are available.
Incorrect Answers:
1: There is no READ ONLY archiving mode in Oracle.
2: For ARCHIVELOG mode online (open) database backups are available also.
3: There is no READ WRITE archiving mode in Oracle.
Oracle 8, DBA Certification Exam Guide, Jason S. Couchman, p. 585-591
Chapter 12: Overview of Backup and Recovery

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