Your girlfriend's mother, a highly attractive woman in her mid-forties, pops by when you're alone in the house. You offer her a drink or two, but it soon becomes obvious that she's flirting with you. Would you:
(a) Make a joke of it and hope your girlfriend comes home soon.
(b) Take her upstairs and give her a good scuttling.
(c) Insist she leaves immediately and warn her that you'll tell her family if she tries any more funny business.