Examine the commands executed in the following sequence：  1：SQL> CREATE ROLE mgrrole；  2：SQL> GRANT create user，select any table，connect，resource TO mgrrole；  3：SQL> GRANT select，update ON sh.sales TO mgrrole；  4：SQL> CREATE ROLE ceo IDENTIFIED BY boss；  5：SQL> GRANT mgrrole，drop any table，create any directory TO ceo；  6：SQL> GRANT ceo TO mgrrole；  Which statement is true about the above commands（）

• A、The commands execute successfully.
• B、Command 6 produces an error because of circular role grant.
• C、Command 5 produces an error because a role cannot be granted to another role.
• D、Command 3 produces an error because the MGRROLE role already contains system privileges.
• E、The table created by HR remains and HR still has the CREATE TABLE system privilege.
• F、The table created by HR remains and HR can grant the CREATE TABLE system privilege to other users.