With no explanation, chose the best option from "A" or "B". John who already made plans for Saturday is talking to his ex wife Nancy  on the telephone when she asks him to help her move on Saturday. John wants to respond to Nancy's request.

A: John tells Nancy that he is just simply too busy on Saturday and already made other plans, so he can't help her.
B: John tells Nancy that he will postpone his plans for a couple of hours and come early to help her out and then leave to go to his planned event.
B.