That's very graceful of you

Hi

Could you please help me with the right phrase here? Any other suggestions please?

(B has given A a task to do for him. When he talks about the money, A says:)

A- I really don't want/need any money for such a little thing.

B - That's very kind of you, but I think...

B - That's very graceful of you, but I think...

B - That's very gracious of you, but I think...

Thanks,

Tom