Explanation:
Oracle will use naming conventions when it creates the OMF files. In this naming convention, %t represents the tablespace name, %u is a unique 8-character string, and %g stands for the redo log group number.
Incorrect Answers:
2: Oracle will create a locally managed tablespaces, so information about a datafile will not be stored inside a data dictionary table.
3: Oracle does not use ALERT.LOG file to store information about datafiles. It just keep log of database events and database structure changes.
4: Initialization parameter file will not be used to store this information. Oracle reads this file to set initialization parameters to start the instance. The structure of the database is stored inside control files. Oracle uses them to mount and open the database.
Reference:
OCP Oracle9i Database: New Features for Administrators, Daniel Benjamin, p. 153-160
Chapter 3: Manageability Enhancements
Oracle 9i New Features, Robert Freeman, p. 2-12
Chapter 1: Oracle9i Database Administration and Management Features

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