An inability to report that the two (2) rows in set B contain the same number of dots by Rebecca reflects a lack of conservation.
Cognitive development refers to the development of learning skills, thought processes, knowledge and problem-solving abilities in living organisms such as humans, especially from infancy through adulthood.
In Psychology, conservation can be defined as a logical thinking ability that allows a living organism to understand that physical quantities such as lines, doesn't change in amount even when their appearance are altered.
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