Carla Was Testing the "A,not B" Error with Her Son,Alex

Multiple Choice

Carla was testing the "A,not B" error with her son,Alex.Carla put a ball under a blue blanket several times,and Alex searched for the ball under the blue blanket.Then Carla put the ball under the yellow blanket,and Alex looked at the yellow blanket but again reached under the blue blanket.This suggests that Alex

A) does not have object permanence.
B) did not know the correct location of the ball.
C) simply ignored the yellow blanket and reached under the blue blanket out of preference.
D) knew the correct location but could not stop himself from reaching under the blue blanket.