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': "All are examples of malignant disorders causing myelofibrosis except ? \nSelect and explain. \nA. Chronic myelogenous leukemia, B. Hairy cell leukemia, C. Hodgkin's disease, D. PNH", 'role': 'user'}, {'content': "Answer: D \nExplanation: Disorders Causing Myelofibrosis Acute leukemia (lymphocytic, myelogenous, megakaryocytic) Chronic myelogenous leukemia Hairy cell leukemia Hodgkin's disease Idiopathic myelofibrosis Lymphoma Multiple myeloma Myelodysplasia Polycythemia vera Systemic mastocytosis Ref: Harrison, E-18,P-905.", 'role': 'assistant'}]