This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Growth, Development, and Behavior, Subject name: Pediatrics
[{'content': 'A child is able to say sentence of 6 words at: \nSelect and explain. \nA. 2 years, B. 3 years, C. 4 years, D. 5 years', 'role': 'user'}, {'content': "Answer: D \nExplanation: d. 5 years(Ref: Nelson's 20/e p 65-77, Ghai 8/e p 52-53)Mnemonic:Between ages of 2 and 5 years, number of words in a typical sentence equals the child's age (e.g. 2 by age 2 year, 3 by age 3 year)So, a child speaks 5 word sentences at 5 years; So, out of the given options 5 years is the best answer.", 'role': 'assistant'}]