Explanation:
If you are running in NO ARCHIVE LOG mode there is only one way to fix media failure: perform a complete restore of all files from last night’s backup. Incorrect Answer:
1: You cannot just restore data files for the SYSTEM table space to recover database if you are running it in NO ARCHIVE LOG mode.
2: All files, including data files and archived redo logs should be restored from last night’s backup.
4: You cannot take the SYSTEM table space offline with database in MOUNT state.
Reference:
OCP Oracle 9i Database: Fundamentals II Exam Guide, Rama Velpuri, p. 303
Chapter 12: User-Managed Complete Recovery

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