text: A<unk>  is a precursor cell to a promegakaryocyte, which in turn becomes a megakaryocyte. It is the beginning of the thrombocytic series.
  It derives from an CFU-Me colony unit of pluripotential hemopoietic stem cells.
option_0: Megakaryoblast
option_1: Megakaryocyte
option_2: Lymphoblast
option_3: Histiocyte
option_4: Proerythroblast
option_5: Immunoblast
option_6: Ameloblast
option_7: Monocyte