Final answer:
Jean Piaget identified the stages children go through as they learn to reason. His theory of cognitive development includes four stages representing the evolving cognitive abilities from infancy to adulthood. Piaget's work is pivotal in understanding childhood development.
Step-by-step explanation:
The psychologist who identified the stages children go through as they learn to reason was Jean Piaget. Piaget proposed a theory of cognitive development that outlines four distinct stages: sensorimotor, preoperational, concrete operational, and formal operational. These stages represent different levels of cognitive abilities that children develop as they grow.
Piaget's theory focuses on children's natural curiosity and the belief that children's thinking evolves qualitatively across these stages. Unlike adults, children do not reason in the same way, hence as they progress from one stage to the next, there is a significant shift in their cognitive processes.
Among the options provided: A. Cooley, B. Freud, C. Mead, and D. Piaget, the correct answer is D. Piaget. He emphasized how the ability to think and reason develops throughout childhood, impacting how individuals interact with and understand the world around them.