单选题检索选修四门以上课程的学生总成绩(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(GRAD FROM SC WHERE GRADE＞=60 GROUP BY S# ORDER BY 2 DESC HAVING COUNT(*)＞=4
B、 SELECT S#, SUM(GRAD FROM SC WHERE GRADE＞=60 GROUP BY S# HAVING COUNT(*)＞=4 ORDER BY 2 DESC
C、 SELECT S#, SUM(GRAD FROM SC WHERE GRADE＞=60 HAVING COUNT(*)＞=4 GROUP BY S# ORDER BY 2 DESC
D、 SELECT S#, SUM(GRADFROM SC WHERE GRADE＞=60 ORDER BY 2 DESC GROUP BY S# HAVING COUNT(*)＞=4

【正确答案】 B

【答案解析】