Aplastic anemia can progress to -a) AMLb) Myelodysplastic anemiac) Pure red cell aplasiad) Paroxysmal nocturnal hemoglobinuriae) Myelofibrosis
Aplastic anemia is a pancytopenia with bone marrow hypocellularity. It can progress to –

Paroxysmal Nocturnal hemoglobinuria
Myelodysplastic anemia
Rarely acute leukemia

Pure 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 by

Marrow fibrosis
Myeloid metaplasia with extramedullary erythropoiesis
Splenomegaly
acd
bcd
abd
ab