Explanation:
The alert log will never contain information about external to the database restore, like an operating system restore of the database files.
Incorrect Answers:
1: The alert log shows what table space was placed in end backup mode.
2: The alert log shows altering the database to take a data file offline.
4: The alert log shows changing the database backup mode from NOARCHIVELOG to ARCHIVELOG.
Oracle 8, DBA Certification Exam Guide, Jason S. Couchman, p. 663-666
Chapter 14: Database Failure and Recovery

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