Hannah is playing with her 7-month-old niece, ellie. she rolls a toy truck toward her and ellie tries to roll it back. one time the truck rolls behind a chair and is out of sight. ellie seems to forget about the truck and about the game they had both enjoyed playing. this is because ellie has not achieved:
a. conservation
b. sensorimotor memory
c. object permanenced. egocentrism

C. Object permanence

Explanation:

This question should be answered looking at the definition of all four phrases:

A. conservation refers not using resources in a wasteful manner.

B. Sensorimotor Memory refers to your muscles and sensorimotor system developing a memory to do certain activities over time.

C. Object permannence refers to the understanding that objects don't disappear just because you cannot see them.

D. Egocentrism is the inability to see something through someone else's perspective.

From looking at the definitions it is clear that the answer is C, since Ellie forgot about the truck as soon as she could no longer see it.

i believe the answer is a.

explanation:

hope my answer has you!