Concept:Vygotsky’s socio-cultural theory states that a child’s development is strongly influenced by social interactions, cultural context, and language.Explanation:Vygotsky argued that every higher mental function appears twice—first on a social level between people, then inside the child. Culture provides the environment in which children grow and think. Language, as a cultural tool, becomes the medium of thought. Children learn by interacting with more knowledgeable others (MKO) within their zone of proximal development (ZPD). Temporary support, called scaffolding, helps them reach higher potential. Hence, culture and language are central to development.Answer:Option A: culture and language play a crucial role in development.