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: Pathology
[{'content': 'Regarding hemostasis, true statement for nitric oxide is \nSelect and explain. \nA. Is a vasoconstrictor, B. Inhibits platelet activating factor-1, C. Inhibits Sinoatrial node, D. Inhibits platelet aggregation', 'role': 'user'}, {'content': 'Answer: D \nExplanation: . Inhibits platelet aggregation', 'role': 'assistant'}]