基于这样的3个表,即学生表S、课程表C和学生选课表SC,它们的关系模式如下:S(S,SN,SEX,AGE,DEPT)(学号,姓名,性别,年龄,系别)C(C,CN)(课程号,课程名称)SC(S,C,GRADE)(学号,课程号,成绩).检索选修课程“C2”的学生中成绩最高的学生的学号。正确的SELECT语句是()
A.SELECT S# FROM SC WHERE C#=C2 AND GRADE>=(SELECT GRADE FROM SC WHERE C#=C2) B.SELECT S# FROM SC WHERE C#=C2 AND GRADE IN(SELECT GRADE FROM SC WHERE C#=C2) C.SELECT S# FROM SC WHERE C#=C2 AND GRADE NOT IN (SELECT GRADE GORM SC WHERE C#=C2) D.SELECT S# FROM SC WHERE C#=C2 AND GRADE>=ALL(SELECT GRADE FROM SC WHERE C#=C2)