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': 'Predisposing factor for arterial thrombosis - \nSelect and explain. \nA. AT III deficiency, B. Proteins S deficiency, C. Protein C deficiency, D. Homocysteinemia', 'role': 'user'}, {'content': 'Answer: D \nExplanation: None', 'role': 'assistant'}]