Explanation:
The correct procedure for multiplexing control files: shut down the database, edit the CONTROL_FILES parameter, copy the control file, and start up the database.
Incorrect Answers:
1: You need first edit the CONTROL_FILES parameter, then copy the control file, not rename the control file.
3: There is no MULTIPLEX_CONTROL_FILES exists. Also you don't need to copy the control file to trace.
4: There is no the ALTER DATABASE MULTIPLEX CONTROLFILE command in Oracle.
Oracle 8, DBA Certification Exam Guide, Jason S. Couchman, p. 571-574
Chapter 12: Overview of Backup and Recovery

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