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': 'Pancytopenia with hypercellular marrow could be due to all, EXCEPT: \nSelect and explain. \nA. Myelodysplasia, B. Paroxysmal nocturnal hemoglobinuria, C. Sarcoidosis, D. Dyskeratosis congenita', 'role': 'user'}, {'content': 'Answer: D \nExplanation: Dyskeratosis congenita is associated with pancytopenia and hypocellular bone marrow. Pancytopenia with hypercellular marrow is seen in: Myelodysplasia Myelofibrosis Hairy cell leukemia Tuberculosis Sarcoidosis Brucellosis PNH Hypocellular Bone marrow +/- Cytopenia: Q fever Legionnaires disease Anorexia nervosa, starvation Mycobacterium', 'role': 'assistant'}]