几道英语方面的题,帮下忙啊1.He is the only student who ( )the exam.A.have

几道英语方面的题,帮下忙啊
1.He is the only student who ( )the exam.
A.have passed B.has passed C.had passed D.has been passed
2.You find it ( )useful to learn even a little english
A.it B.it was C.that D.this
3.Can you tell me (
A.who is he B.he is who C.who′s this D.who he is