【单选题】在关系stu(sno,sname,sage,ssex,sdept),sc(sno,cno,grade),查询"张红"同学的所有成绩,SQL语句为()
A.
select sname,grade from stu where sname='张红'
B.
select sname,grade from stu,sc where sname='张红'
C.
select sname,grade from stu,sc where stu.sno=sc.sno and sname='张红'
D.
select sname,grade from stu,sc where stu.sno=sc.sno , sname='张红'