Piaget's stages of cognitive development are:

• A. Sensorimotor; Preoperational; Formal Operational; Concrete Operational
• B. Preoperational; Sensorimotor; Concrete Operational; Formal Operational
• C. Sensorimotor; Concrete Operational; Preoperational; Formal Operational
• D. Sensorimotor; Preoperational; Concrete Operational; Formal Operational

Answer: (D)

Piaget's stages unfold from sensorimotor to formal operational, showing a progression from concrete experiences to abstract reasoning. In the sensorimotor stage (birth to about 2 years), infants learn through actions and senses and develop object permanence. In the preoperational stage (roughly ages 2–7), children gain symbolic thought but still struggle with egocentrism and lack conservation. In the concrete operational stage (about 7–11), they start using logical operations on concrete objects, understand conservation, and can decenter. In the formal operational stage (adolescence onward), they reason abstractly, think hypothetically, and plan systematically.

This progression is why the sequence starting with sensorimotor, then preoperational, then concrete operational, and finally formal operational is correct. Placing a later capability before an earlier one contradicts observed development, since abstract reasoning doesn’t emerge until after concrete logical operations are in place, and object permanence is established long before symbolic thought.