<prompt> Aplastic anemia can progress to -a AMLb Myelodysplastic anemiac Pure red cell aplasiad Paroxysmal nocturnal hemoglobinuriae Myelofibrosisacdbcdabdab  <response>: Aplastic anemia is a pancytopenia with bone marrow hypocellularity. It can progress to Paroxysmal Nocturnal hemoglobinuriaMyelodysplastic anemiaRarely acute leukemiaPure red cell aplasia is a selective disease of absence of erythrocyte progenitor cells. In contrast to aplastic anemia and MDS, the unaffected lineage WBC and platelets appear quantitatively and qualitatively normal.Myelofibrosis is a clonal disorder of a multipotent hematopoietic progenitor cell of unknown origin and is characterized byMarrow fibrosisMyeloid metaplasia with extramedullary erythropoiesisSplenomegaly 