【单选题】学生表S、课程表C和学生选课表SC,它们的结构如下:S(S#,SN,SEX,AGE,DEPT)C(C#,CN)SC(S#,C#,GRADE)其中,S#为学号,SN为姓名,SEX为性别,AGE为年龄,DEPT为系别,C#为课程号,CN为课程名,GRADE为成绩。查询选修4门以上的课程的学生总成绩(不统计不及格的课程),并要求按总成绩的降序排列出来。正确的SELECT语句是
A.
SELECT S# , SUM (GRADE) FROM SC WHERE GRADE>=60 GROUP BY S# ORDER BY 2 DESC HAVING COUNT (*) >=4
B.
SELECT S# , SUM (GRADE) FROM SC WHERE GRADE>=60 GROUP BY S# HAVING COUNT (*) >=4 ORDER BY 2 DESC
C.
SELECT S# , SUM (GRADE) FROM SC WHERE GRADE>=60 HAVING COUNT (*) >=4 GROUP BY S# ORDER BY 2 DESC
D.
SELECT S# , SUM (GRADE) FROM SC WHERE GRADE>=60 ORDER BY 2 DESC HAVING COUNT (*) >=4 GROUP BY S#