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': 'The differential diagnosis for pancytopenia with cellular bone marrow include the following except - \nSelect and explain. \nA. Megaloblastic anemia, B. Myelodysplasia, C. Paroxysmal Nocturnal Hemoglobinuria, D. Congenital dyserythropoietic anemia', 'role': 'user'}, {'content': 'Answer: D \nExplanation: None', 'role': 'assistant'}]