Explanation:
If a database file was accidentally deleted or there is a head crash on the disk containing a database file, both these event cause a media failure.
Incorrect Answers:
1: It's the instance failure if the server computer loses power.
2: It's the user error if a table is accidentally truncated.
3: It's the user error if the user issues an abnormal interrupt.
5: It's the application error if there is a logic error in the application.
Oracle 8, DBA Certification Exam Guide, Jason S. Couchman, p. 675-688
Chapter 14: Database Failure and Recovery

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