Answer:
The infant lacks object permanence.
Step-by-step explanation:
The idea of object permanence serves an important part in the cognitive development theory developed by psychologist Jean Piaget. The word "object permanence" refers to explain the capacity of a child to realize that objects still exist, even though they can not be seen or heard any longer. This implies the capability of constructing an object's mental image. As per the question, the child forgets about the toy as soon as it got covered by the blanket and it signifies that he lacks the object permanence.