Answer:
Concept of Conservation
Explanation:
Concept of conservation is the cognitive ability that helps a child to judge that some properties such as number of items, or volume will remain the same and invariant even if the shape or size of the container is changed or adjusted. This concept was posited by Jean Piaget, a psychologist who noted this ability in children between ages 7 to 11 during their concrete operational stage. He posits that the cognition of these age group will only focus on the noticeable attributes (e.g numbers, volume lenght) of an object rather than any change in size or other attributes
In this question the child lacks the concept of conservation with the inability to judge that the two beakers contain clearly identical volume of a liquid.