Concept:Vygotsky viewed private speech as a tool for self-guidance, not a sign of egocentrism. It helps children regulate their actions during challenging tasks.Explanation:Vygotsky believed children learn through social interaction. As they acquire language, they start talking to themselves. This private speech helps them plan and control their behavior. It is especially useful when doing complex tasks. Over time, private speech becomes silent inner speech. It does not hinder actions nor indicate that cognition is never internalized. Instead, it shows the transition from social to internal thought. Therefore, private speech supports self-regulation, not egocentrism.Answer:C. helps children to regulate their behaviour while doing complex tasks.