Correct Response: A. Researchers have found evidence that children are able to apply adult-like grammar structures creatively at a young age (approximately 2–2.5 years of age/telegraphic stage) and produce unique sentences using a range of sentence types. C and D emphasize memorization of language or situation-specific vocabulary rather than "novel" or creative production on the part of the child, making those answers incorrect. B is incorrect because it highlights a creative activity but not one that necessarily applies universal language principles.
