设有关系模式：SC(sno，cno，grade)，各属性含义依次是学号、课程号、分数。要查询分数低于60分的学生学号，正确的SQL语句是______。 A: SEI，ECT sno FROM SC WH ERE grade BETWEEN O AND 60 B: SELECT sno FROM SC WHERE grade＜60 C: SELECT sno FROM SC HAVlNG grade BETWEEN O AND 60 D: SELECT sno FROM SC HAVING grade＜60