Explanation:
The structure of the DEPT table will be displayed because the CREATE TABLE statement is DDL operation and it cannot be rolled back because implicit commit occurs on the database when a user exits SQL*Plus or issues a data-definition language (DDL) command such as a create table statement, user to create a database object, or an alter table statement, used to alter a database object.
Incorrect Answers:
2: The ROLLBACK statement has nothing to do with the storage space of the DEPT table.
3: The DESCRIBE DEPT statement does not produce the error. It displays the structure of the DEPT table.
4: The COMMIT statement does not need to be introduced because implicit commit occurs on the database after creation of the table.
OCP Introduction to Oracle 9i: SQL Exam Guide, Jason Couchman, p. 281-283
Chapter 6: Manipulating Oracle Data

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