Question

If the genotypes determining the blood groups of a couple are $I^A{I}^O$ and $I^A{I}^B$, then the probability of their first child having type O blood is is

• A. 0
• B. 0.25
• C. 0.50
• D. 0.75

Answer 1

Answer: (A)

The genotype of child having blood group-0 with parents having $I^A{I}^O$ and $I^A{I}^B$ blood groups can be represented as

From the above cross, it is shown that none of the off springs will be of blood group-O.
$\therefore$ The probability of their first child having type-0 blood is zero