With no explanation, chose the best option from "A" or "B". Frank is at home relaxing when his sister Martha calls him to ask him to watch her kids while she goes out. Frank wants to respond to his sister's request for babysitting.

A: Frank tells his sister that he'll be over right after he gets ready.
B: Frank tells his sister that he's relaxing now, so he's not able to come over and help.
A.