A child was born with blood type B. Three candidate fathers, X, Y, and Z, were found to have blood types A, B, and O, respectively. Which of the candidate fathers cannot be a blood donor to the child above?

Question

Quizplus · Accepted Answer

candidate X. Blood with the A antigen will cause an immune response if donated to an individual with the B antigen.
Key Takeaway: Blood can only be donated to an individual if that blood will not cause an immune reaction in the recipient. Since O type blood does not possess any antigens, it will not cause an immune response and can be donated to anyone regardless of blood type. Since the child has blood type B, he or she can receive blood from an individual with blood type B. Blood with only the A antigen will cause an immune reaction in the recipient, and cannot be used for a blood donation.

A Child Was Born with Blood Type B