Explanation:
There are three types of backups can be performed: hot backups with open database, operating system backups with close database and online control file backups using the ALTER DATABASE BACKUP CONTROLFILE command.
Incorrect Answers:
3: There is no ALTER CONTROLFILE BACKUP command in Oracle, you can backup online control file with ALTER DATABASE BACKUP CONTROLFILE command.
4: There is no ALTER DATABASE BACKUP TABLE SPACE command in Oracle, you can put the table space in backup mode with ALTER TABLE SPACE BEGIN BACKUP command, copy datafiles of the table space and return table space in normal mode with ALTER TABLE SPACE END BACKUP command. Oracle 8, DBA Certification Exam Guide, Jason S. Couchman, p. 577-583
Chapter 12: Overview of Backup and Recovery

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