Query (let me give you a hand, ...?)

[newbie]

Hi,
Please tell me which should be chosen here:

Let me give you a hand, ...?
a. shall I
b. shall we
c. will you
d. won't you

(I think either c or d is correct)

Many thanks
Newbie.

[Anglika]

I agree with #d, and have heard #c occasionally.