hello there
your answer to this is:ABO blood group
EXPLATION: ABO blood group system, the classification of human bloods based on the inherited properties of it's red blood cells (erythrocytes) as determined by the presence or the absence of the antigens A and B, which are carried on the surface of the red cells . Persons may this have type of A, type B, type O, or type AB blood inside the blood inside a human.
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FaithRawlins14