Top Five Terrifying Female Villains

I did a post about my favourite books with terrifying female villains. It's for Shepherd. They do book recommendations based on super-fun metrics and I can highly recommend getting lost there. Don't go unless you've got some time to waste. Of course I wrote these recommendations in pursuit of selling my first thriller, Mother's Day.

Here is my list. Which of these baddies is the scariest, and why? Please discuss.