Ooh, this one is tricky... The first one seems to be true by sheer absurdity, and the latter two seem so obvious that I feel you may be trying to deceive via wordplay. The first is the most obvious choice at first glance, but could it be a red herring...?

[A moment as she considers the possibilities.]

I believe I'll go with the third, on the caveat that you yourself are claiming to be the better mother.