It's suggested that some activities _____ to celebrate the 30th anniversary of the Reform and Opening-up.[ ]

A. should hold

B. are held

C. be held

D. will be held

实现“取消用户USER4对学生表STUD中学号(XH)的修改权限”这一功能的SQL语句是( )。

A. REVOKE UPDATE (XH)
ON TABLE FROM USER4;
B. REVOKE UPDATE (XH)
ON TABLE STUD FROM PUBLIC;
C. REVOKE UPDATE (XH)
ON TABLE STUD FROM USER4;
D. REVOKE ALL PRIVILEGES
ON TABLE STUD FROM USER4;