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: Surgery
[{'content': 'The deficiency of all of the following factors increases the incidence of thrombus formation except ? \nSelect and explain. \nA. Lipoprotein A, B. Protein - C, C. Anti - thrombin III, D. Protein - S', 'role': 'user'}, {'content': "Answer: A \nExplanation: Ans. is 'a' i.e., Lipoprotein A", 'role': 'assistant'}]