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 may be seen due to all of the following except: \nSelect and explain. \nA. Myelodysplasia, B. Paroxysmal Nocturnal Hemoglobinuria, C. Dyskeratosis congenita, D. Sarcoidosis', 'role': 'user'}, {'content': 'Answer: C \nExplanation: Answer is C (Dyskeratosis Congenita ) Dyskeratosis congenita (constitutional aplastic anemia) is associated with Pancytopenia and a Hypocellular bone marrow Myelodysplasia, PNH and Sarcoidosis may all be associated with Pancytopenia and a cellular bone marrow', 'role': 'assistant'}]