Explanation:
This command is alternate command to start your Oracle9i database. The Server Manager is not supported in Oarcle9i any more, so you need to use SQL*Plus for administration tasks, as start or stop of database, also.
Incorrect Answers:
1: The NOLOG option must be used to run this script because the instance is not started yet.
2: Script that need to be executed can be started with @ symbol, not with –S.
3: The S option cannot be used to run the startmydb.sql script.
Reference:
OCP Oracle9i Database: New Features for Administrators, Daniel Benjamin, p. 4-10
Chapter 1: Security Enhancements
Oracle 9i New Features, Robert Freeman, p. 132-139
Chapter 5: Miscellaneous Oracle9i Features and Enhancements

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