Which is the first stage of erythrocytic maturation in which the cytoplasm is pink due to the formation of hemoglobin?

The first stage of erythrocytic maturation where the cytoplasm begins to appear pink due to the formation of hemoglobin is the polychromatic normoblast. At this stage, the developing red blood cells (RBCs) have accumulated enough hemoglobin, which imparts a pinkish hue to the cytoplasm.

During erythropoiesis, the maturation process involves several stages starting from the pronormoblast. As cells mature, they transition through the basophilic normoblast stage, which is characterized by a blue cytoplasm due to the high amount of ribosomal RNA. This changes as hemoglobin production increases in the polychromatic normoblast stage, introducing the pink characteristic.

The reticulocyte stage follows and features a more mature form of erythrocyte, but by that time, the cytoplasmic color is more distinctly pink due to the very high concentration of hemoglobin and the loss of organelles. Therefore, the polychromatic normoblast stage specifically marks the transition when the pink hue begins to develop, making it the correct answer.