Explanation:
To fix problem with corrupted current online redo log file after instance crash you need to perform a time-based recovery that stops at the time that the current online redo log became corrupt and open the database after that.
Incorrect Answers:
1: A time-based recovery needs to be done, not table space recovery, in this situation.
2: You don't need recover the SYSTEM table space.
3: You need to perform an incomplete time-based recovery, not a complete recovery.
4: You must perform a time-based recovery, don't skip it before RESETLOGS option.
Oracle 8, DBA Certification Exam Guide, Jason S. Couchman, p. 704-711
Chapter 15: Advanced Topics in Data Recovery

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