Five-month-old Stewart enjoyed repeatedly shaking his rattle in new and innovative ways in order to hear the different sounds each new movement made. According to Piaget, Stewart is demonstrating a:a. simple reflex. b. secondary circular reaction. c. primary circular reaction. d. tertiary circular reaction.

secondary circular reaction

Explanation:

secondary circular reaction is the behavior response observed in child with age four to eight months. The child in this age group become able to perceive external object and they start interacting to object around him.  The common behavior expressed in this reaction is that the child repeat actions which gives them sense of pleasure and there is involvement of his own body and external object as well.

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