Explanation:
You cannot roll back DROP TABLE statement. All pending transactions related on this table are committed. If the table is dropped, Oracle automatically drops any index, trigger and constraint associated with the table as well. All data in the table is deleted, and the table structure is also deleted.
Incorrect Answers:
3: All views based on the DEPT table become invalid, but they are not deleted.
6: All data in the table is deleted, and the table structure is also deleted. Command TRUNCATE deletes all data in the table, but does not delete the structure of the table.
7: All synonyms based on the DEPT table are not deleted after dropping the table.
OCP Introduction to Oracle 9i: SQL Exam Guide, Jason Couchman, p. 225
Chapter 5: Creating Oracle Database Objects

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