AExplain Why an Organ Transplant Made Between a Donor of Blood

Essay

A.Explain why an organ transplant made between a donor of blood group AB and a recipient of blood group O will always be rejected,even if it is perfectly HLA-matched and the recipient has been given immunosuppressant drugs.What is this type of rejection called?
B.Give another example of ABO incompatibility between donor and recipient that would lead to this type of rejection.
C.What other antigen incompatibilities,other than those of blood group,are most likely to provoke this type of rejection?
D.Which pre-surgical laboratory test should be performed to prevent this type of rejection?