But a more serious answer to your question is this:
I don't CARE about rankings!!!! I care about how well we do in the PAC-12. I want to WIN the PAC-12 South so we can have a chance to go to the Rose Bowl! And if we lose the PAC-12 Championship game, there's a chance we'd go to the Rose Bowl anyway, if the winner of the PAC-12 Championship got into the National Title game.
Rankings be damned. I want to go to the Rose Bowl! The rankings will take care of themselves. A great ranking doesn't get you diddly squat if you can't go to a good bowl game.
So you'd rather have more overall wins than a loss to the Cougars, then fewer overall wins and a victory over the Cougars. Is that what you are saying? That sounds a lot like my choice A, does it not?