Answer:
The correct answer is - A. 25%.
Step-by-step explanation:
In humans, the blood group system is known as the ABO system where blood groups A and B are codominant and O blood group is recessive. The genotype of the A blood group could be AA or AO similarly for the B blood group genotype would be BB or BO, for the O blood group OO whereas for the AB blood group both A and B alleles should be present together.
Cross: AB blood type father with an A blood type mother (genotype AO)
Gametes: A, B and A, O
Punnett square:
A B
A AA AB
O AO BO
Here, there are 25% chances of AB blood group offspring 50% for the A blood group (AA and AO) and 25% B blood group (BO).