---Let's go to the library, shall we?

---________?

1. A.
   No, I can't
2. B.
   Yes, I wil
3. C.
   Yes, thank you
4. D.
   No, we'd better not

[　　]

—My brother and I will go to the library tomorrow.
—    . Shall we go together?

—My brother and I will go to the library tomorrow.
—     . Shall we go together?

—My brother and I will go to the library tomorrow.

—     . Shall we go together?

A．So do I            B．So I do            C．So will I           D．So I will