Hilda, Age 14 Months, Will Search for an Object When

Hilda, age 14 months, will search for an object when she sees it being moved but will stop searching if she does not see the object being hidden. How should her parents respond?

A) They should give Hilda more practice at finding objects without her seeing their hiding spot be changed because she should have mastered this skill by now.
B) They should consult their pediatrician because Hilda should have mastered this skill before she turned one year of age.
C) They should not be too concerned because this pattern of behavior is characteristic of her age group, according to Piaget.
D) They should consult their pediatrician because this is an indication that Hilda has not acquired object permanence, which she should have done this by 12 months of age.