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 of the following has proved antithrombotic property : \nSelect and explain. \nA. Gelatin, B. Dextran 40, C. Dextran 100, D. Hexastarch', 'role': 'user'}, {'content': 'Answer: B \nExplanation: None', 'role': 'assistant'}]