Explanation:
The ALTER DATABASE BACKUP CONTROLFILE TO TRACE command creates a text backup of the control file.
Incorrect Answers:
2: There is no ALTER DATABASE BACKUP CONTROLFILE TO BACKUP command in Oracle.
3: The ALTER DATABASE BACKUP CONTROLFILE TO 'filename' command will create a binary copy of the control file in the file with name 'filename'.
4: There is no ALTER DATABASE BACKUP CONTROLFILE TO TEXT 'filename' command in Oracle.
Oracle 8, DBA Certification Exam Guide, Jason S. Couchman, p. 591-593
Chapter 12: Overview of Backup and Recovery

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