Answer: Their children may have all the blood types except type O.
Explanation: In the ABO system, blood type are classified based on the type of antigens present in the blood. There are basically two types of antigens: antigen A and B. Blood type A has antigen A, blood type B has antigen B, blood type AB has both A and B antigens while blood type O has neither A nor B antigen. According to genetics, the blood types are controlled by a pair of gene known as genotype. A person with blood type A will have two possible genotypes: iAiA or iAiO while a person with blood type AB will have one possible genotype: iAiB. The possible blood type of their children are A, B, and AB, because each offspring will inherit one antigen from each parent. Therefore, there is possibility of the offsprings having only antigen A which is equal to blood type A or only antigen B which is equal to blood type B or both antigen A and B which is equal to blood type AB.
