Genotype of a person with blood group-B may be $I^{B}I^{B}$ or $I^{O}I^{B}$, person with genotype $I^{B}I^{B}$ can not produce offsprings with blood group-O in any case but if the person’s genotype is $I^{O}I^{B}$, then its offsprings may have blood group-O. eg, [image:5d_image27.jpeg]