Could we go down the immaculate conception route with this one? We could do with a new messiah.
Or even the "well it must have been those aliens that beamed you up and erased all memory of it" answer and suggest she looks up the Alien Burt episodes of the all time great series Soap
However in a rare serious moment
this does sound like a real someone in deep shit, we shouldn't make it worse. People cheating on their homework are much better targets.