A) Circular reaction is a term used by Piaget to describe repetitive actions that infants engage in for the sake of exploring their environment. B) Circular reaction is a term used by Piaget to describe the state of confusion and cognitive disequilibrium that occurs when a child encounters new information that doesn't fit with their existing mental schema. C) Circular reaction is a term used by Piaget to describe the understanding of object permanence in infants. D) Circular reaction is a term used by Piaget to describe the sensorimotor stage of cognitive development.