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（）
- AThe commands execute successfully.
- BCommand 6 produces an error because of circular role grant.
- CCommand 5 produces an error because a role cannot be granted to another role.
- DCommand 3 produces an error because the MGRROLE role already contains system privileges.
- EThe table created by HR remains and HR still has the CREATE TABLE system privilege.
- FThe table created by HR remains and HR can grant the CREATE TABLE system privilege to other users.