[单选题]CREATE TABLE dept (deptno NUMBER(2), dname VARCNAR

AThe DESCRIBE DEPT statement displays the structure of the DEPT table.

BThe ROLLBACK statement frees the storage space occupies by the DEPT table.

CThe DESCRIBE DEPT statement returns an error ORA-04043: object DEPT does not exist.

DThe DESCRIBE DEPT statement displays the structure of the DEPT table only if there is a COMMIT statement introduced before the ROLLBACK statement.