The most popularly known blood grouping is the grouping. It is named and not ABC, because "O" in it refers to having :-
(A) No antigens A and B on RBCs
(B) Other antigens besides A and B on RBCs
(C) Overdominance of this type on the genes for A and B types
(D) One antibody only - either anti–A or anti–B on the RBCs
