Explanation:
The loss of SYSTEM table space datafiles or datafiles from table spaces containing rollback segments may cause Oracle to stop running. In this situation, full recovery using backup copies of all database files is required. The database cannot be open during recovery. Media failure will most likely be accompanied by disk failure, which you will need to have fixed.
Incorrect Answers:
1: You cannot do in this situation complete recovery for mounted database.
2: You cannot do in this situation complete recovery for opened database: loss or damage of SYSTEM table space may not allow to Oracle instance to open the database.
3: You cannot do in this situation complete recovery for opened or closed database.
Oracle 8, DBA Certification Exam Guide, Jason S. Couchman, p. 676
Chapter 14: Database Failure and Recovery

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