Concept:Private speech is talking to oneself out loud or silently. Vygotsky saw it as a tool for self‑regulation, not egocentrism.Explanation:Children use private speech to guide and organize their thinking. It helps them plan actions, solve problems, and control behaviour. Through verbalising thoughts, learners improve cognitive skills and focus. Vygotsky argued that private speech does not hinder thinking. It also does not increase egocentrism. Instead, it supports internalisation of social speech into inner thought. This process boosts self‑monitoring and reasoning. Therefore, private speech actively assists students in regulating their own mental processes.Answer:A. helps the students to regulate their thinking.