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: Medicine
[{'content': 'Complication of long-term hemophilia   a) Joint deformity  b) Transfusion transmitted disease  c) Renal calculi  d) Severe iron deficiency anemia \nSelect and explain. \nA. ab, B. bc, C. bd, D. ad', 'role': 'user'}, {'content': 'Answer: A \nExplanation: None', 'role': 'assistant'}]