数据库中有两张表student(stuid,stuname,stuage),score(stuid,subject,marks).请分析下面哪些查询可查找出参加过考试的学生姓名?( )【多选】
ASelect stuname from student where stuid in(select stuid from score)
BSelect stuname from student,score where student.stuid=score.stuid
CSelect stuname from student left outer join score on student.stuid=score.stuid
DSelect stuname from student where exists (select * from score where student.stuid=score.stuid)