Explanation
The correct answer is D: O.
The ABO blood group system is determined by the presence or absence of antigens A and B on the surface of red blood cells. The four blood groups in this system are A, B, AB, and O.
A child inherits one ABO blood group gene from each parent. The A and B alleles are codominant, while the O allele is recessive. This means that if an individual has one A allele and one B allele, they will have the AB blood group.
In the case of a child with a mother of blood group A and a father of blood group AB, there are three possible genotypes for the child: AA, AB, and AO.
If the child inherits the A allele from the mother and the B allele from the father, they will have the AB blood group.
If the child inherits the A allele from the mother and the A allele from the father, they will have the A blood group.
If the child inherits the A allele from the mother and the O allele from the father, they will have the A blood group.
If the child inherits the O allele from both parents, they will have the O blood group.
Therefore, the child will not have the AB blood group, but they could have the A, B, or O blood group depending on their genotype.
