Answer:
Option D
Step-by-step explanation:
Given
Justin has type A blood . Both the parents of Justin has AB blood type
Brittany has type B blood and both the parents of Brittany has AB blood type
This make it clear that -
Genotype of Justin is AA
Genotype of Brittany is BB
Now if Justin is crossed with Brittany , following blood groups in offspring is possible -
AA * BB
AB, AB, AB, AB
Thus, none of the offspring will have A blood group. Thus the chances that Justin and Brittany's son has type A blood is
%
Option D is correct