A young man excitedly tells his mother he's fallen in love and is going to get married.
He says, "Just for fun, Ma, I'm going to bring over 3 women and you try and guess which one I'm going to marry."
The mother agrees.
The next day, he brings three beautiful women into the house and sits them down on the couch and they chat for a while. He then says, "Okay, Ma, guess which one I'm going to marry."
She immediately replies, "The one in the middle."
"That's amazing, Ma. You're right. How did you know?"