The four substages of Piaget's sensorimotor stage include primary circular reactions, secondary circular reactions, coordination of reactions, and tertiary circular reactions. This describes which overall stage?

• A. Preoperational
• B. Sensorimotor
• C. Concrete operational
• D. Formal operational

Answer: (B)

These stages come from Piaget’s sensorimotor period, the time when infants learn primarily through physical interaction with the world. The sequence described—repeating actions centered on the body (primary circular reactions), then repeating actions with objects (secondary circular reactions), then combining actions to achieve a goal (coordination of reactions), and finally exploring new ways to manipulate objects (tertiary circular reactions)—all falls inside this sensorimotor window, which lasts from birth to about two years old.

This is distinct from the preoperational stage, which focuses on emerging symbolic thought and language around ages 2 to 7; and from the concrete operational stage, which involves logical thinking about concrete objects (roughly ages 7 to 11); as well as the formal operational stage, which introduces abstract reasoning (adolescence onward). The described behaviors reflect learning through action and discovery typical of infancy, not the later stages that rely more on mental representation and higher-order reasoning.