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: Anatomy
[{'content': 'The Haversian system is found in: \nSelect and explain. \nA. Diaphysis of long bones, B. Cancellous bone, C. Epiphysis, D. Spongy bones of children', 'role': 'user'}, {'content': 'Answer: A \nExplanation: A i.e. Diaphysis of long bones', 'role': 'assistant'}]