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: Pharmacology
[{'content': 'Which is not an antiplatelet drug \nSelect and explain. \nA. Aspirin, B. Streptokinase, C. Clopidogrel, D. Ticlodipine', 'role': 'user'}, {'content': 'Answer: B \nExplanation: Streptokinase obtained from\xa0β - hemolytic streptococci activates plasminogen to form plasmin and breaksdown Fibrin.', 'role': 'assistant'}]