This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: None, Subject name: Forensic Medicine
[{'content': 'At what age, does the bih length doubles: UPSC 07; FMGE 10, 11 \nSelect and explain. \nA. 1 year, B. 2 years, C. 3 years, D. 4 years', 'role': 'user'}, {'content': 'Answer: D \nExplanation: Ans. 4 years', 'role': 'assistant'}]