Which theory identifies stages such as sensorimotor, preoperational, concrete operational, and formal operational?

• A. Piaget's theory.
• B. Erikson's theory.
• C. Kohlberg's theory.
• D. Vygotsky's theory.

Answer: (A)

These stage names come from Piaget's theory of cognitive development, which describes how children's thinking evolves in distinct qualitative stages. In the sensorimotor stage, from birth to about two years, infants learn through direct sensory and motor interaction with the world and gradually develop object permanence. In the preoperational stage, roughly ages two to seven, children begin to use language and symbols but think egocentrically and struggle with understanding others’ viewpoints and conservation. In the concrete operational stage, about seven to eleven, children gain logical thinking about concrete objects and events, understand reversibility and conservation, and can consider different perspectives with concrete examples. In the formal operational stage, starting around adolescence, they develop abstract reasoning, hypothetical-deductive thought, and the ability to formulate and test hypotheses independent of concrete objects.

Other theorists describe different frameworks: Erikson emphasizes psychosocial stages and emotional-social conflicts across the lifespan; Kohlberg focuses on stages of moral development; Vygotsky highlights the role of social interaction and cultural tools, with learning occurring through guidance and the zone of proximal development rather than fixed age-based stages. The hallmark sequence of sensorimotor through formal operational thinking specifically points to Piaget.