Miles Sees a Friend at the Mall He Hasn't Spoken

Miles sees a friend at the mall he hasn't spoken to in a few years. She is pushing a baby in a stroller. Miles assumes it is a girl because the yellow blanket in the stroller. "She is so beautiful"! When Miles's friend informs him the baby is a boy, Miles says, "Oh, of course. Just look at how strong he is"! Which of the following terms best describes his apparent change in perception with regard to the baby's sex?

A) Bias
B) Stereotype
C) Context
D) Perceptual set