在学生选课数据库中,查询平均成绩大于等于60分的同学,SQL语句为( )
A.
SELECT Sno, AVG(Grade) FROM SC GROUP BY Sno HAVING AVG(Grade)>=60;
B.
SELECT Sno FROM SC WHERE Grade>=60 GROUP BY Sno;
C.
SELECT Sno, Grade FROM SC GROUP BY Sno HAVING AVG(Grade)>=60;
D.
SELECT Sno FROM SC GROUP BY Sno HAVING Grade >=60;