Evaluate the set of SQL statements: CREATE TABLE dept (deptno NUMBER(2), dname VARCNAR2(14), 1oc VARCNAR2 (13)); ROLLBACK; DESCRIBE DEPT What is true about the set?（）
- A The DESCRIBE DEPT statement displays the structure of the DEPT table.
- B The ROLLBACK statement frees the storage space occupies by the DEPT table.
- C The DESCRIBE DEPT statement returns an error ORA-04043: object DEPT does not exist.
- D The DESCRIBE DEPT statement displays the structure of the DEPT table only if there is a COMMIT statement introduced before the ROLLBACK statement.