Answer:
In humans, blood group is determined by three alleles \(I^{A}\), \(I^{B}\), and \(i\).
\(I^{A}\) and \(I^{B}\) are co-dominant whereas \(i\) is recessive to other two.
Thus, if a person with blood group O produces offspring with blood group B then the other parent must contain \(I^{B}\) allele.
The genotype of other person can be \(I^{A}I^{B}\), \(I^{B}I^{B}\), or \(I^{B}i\).
There is only one condition in which the person can have offspring with blood group O that is, when the other parent is \(I^{B}i\).
In this condition, the probability of an offspring to have blood group O is 50%.
In other conditions, the probability of an offspring to have blood O is 0%.
