Explanation:
You can use RMAN with Block Media Recovery to restore and recover only those blocks. It is not required to set the individual data file offline. BMR enables you to back up specific blocks in a datafile without taking the database offline. The default backup method is datafile media recovery. You use the new BLOCKRECOVER statement to perform BMR.
Incorrect Answers:
1: With corrupted blocks you cannot rebuild the index. You need restore and recover these blocks.
2: It is not required to take the individual data file offline to perform the blocks restore and recovery.
4: It is not required to take the individual data file offline to perform the blocks restore and recovery.[/code] Reference:[/code] OCP Oracle9i Database: New Features for Administrators, Daniel Benjamin, p. 186[/code] Chapter 3: Manageability Enhancements[/code] Oracle 9i New Features, Robert Freeman, p. 84-86[/code] Chapter 3: New Oracle9i Availability and Recoverability Features

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