Anthony Is 4 Months Old

Anthony is 4 months old. What behaviors might suggest the formation of a preference for the object of his attachment?

A) Anthony smiles more at the object of attachment than at a stranger.
B) Anthony asks to go along whenever the object of attachment goes on an errand.
C) Anthony follows the object of attachment around the house by creeping and crawling.
D) Anthony finds comfort in holding a scarf that belongs to the object of attachment.