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': 'A patient has the following findings-splenomegaly, low RBC count, normal WBC, and platelet count and peripheral blood smear shows tear drop cells. Repeated BM aspiration is unsuccessful. The probable diagnosis is: \nSelect and explain. \nA. Thalassemia, B. Chronic myeloid leukemia, C. Iron deficiency anaemia, D. Myelofibrosis', 'role': 'user'}, {'content': 'Answer: D \nExplanation: Answer is D (Myelofibrosis) Presence of dry tap (unsuccessful aspiration), tear drop cells and splenomegaly all suggest a diagnosis of myelofibrosis.', 'role': 'assistant'}]