若用如下的SQL语句创建了一个STUDENT表：
CREATE TABLE STUDENT(SNO C(4) PRIMARY KEY NOT NULL，;)
NAME C(8) NOT NULL，;
SEX C(2)，;
AGE N(2))
下列的SQL语句中可以正确执行的是
A．INSERT INTO STUDENT VALUES('1031','王小平', '男',23) B．INSERT INTO STUDENT VALUES('1031',.NULL., '男',23) C．INSERT INTO STUDENT VALUES('1031','王小平',.NULL.,.NULL.) D．INSERT INTO STUDENT VALUES(.NULL.,'王小平','男',23)