Suppose you watch a mother and her infant son playing "peek-a-boo." Now the mother stops playing and breaks off all communication with the little boy, looking away and not responding to his actions. If this infant responds in a typical way, what will he most likely do?
◦ sit calmly, maintaining eye contact, and wait for the mother to "re-engage" with him
◦ become "happier" and more energetic in an attempt to win back the mother's attention
◦ fall asleep
◦ look away and become upset