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': 'Xiphoid process fuses with body of sternum by: \nSelect and explain. \nA. 10 years, B. 20 years, C. 30 years, D. 40 years', 'role': 'user'}, {'content': 'Answer: D \nExplanation: 40 years', 'role': 'assistant'}]