This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: C.V.S., Subject name: Pediatrics
Pancytopenia with hypocellular bone marrow seen in: 
Select and explain. 
A. Fanconi's anemia, B. Paroxysmal nocturnal hemoglobinuria, C. Hairy cell leukemia, D. Myelopthisis
A: Fanconi's anemia
Answer: A: Fanconi's anemia 
Explanation: a. Fanconi's anemia(Ref: Nelson's 20/e p 2362-2371, Chai 8/e p 345-347)Fanconi's anemia shows pancytopenia with hypocellular bone marrow while others in the options cause hypercellular bone marrow.