Answer:
The genotype ratio would be 1:1:1:1
Step-by-step explanation:
If a mother has the genotype Iai and a father having AB blood group is crossed than all four offspring would have different genotype.
IA IB
IA IAIA IAIB
i IAi IBi
So out of four offspring first have genotype IAIA, second have genotype IAIB, third have genotype IAi, and fourth have genotype IBi. Therefore the genotype ratio would be 1:1:1:1. Out of four offspring two would have A blood group, one would have AB blood group and one would and B blood group.