If he's single, B is the clear winner. It puts you on your home turf. The trick is sounding disinterested enough to get him to wonder why, but not so disinterested that he doesn't think you have any interest at all.
Sexy attire and action without being obvious and transparent is the key. For example, clothes where your breasts are pretty well highlighted (or better could just "fall out by accident", or he gets a quick, "accidental" flash) and other things along those lines will really help your case.
All I can say is that this would work on me. I would already be a little curious why you had invited me over, but seeing parts of your body again that I might miss would help me make the decision that I might want to try again...
I must warn you, though, I can't speak for your ex, as I don't know his sex drive or your level of activity in the relationship, but the best way to a man's heart is through his pants, and that hold true for a good majority of guys.