AB bloodgroup is caleed universal acceptor, but if a person with A bloodgroup will donate his blood, it will have antibody B, which can react with antigen B, still why AB bloodgroup is known as universal acceptor?

A person with AB blood group has both antigen A and B and if a person with A blood group (A antigen) donates blood then it would not produce antibodies because the acceptor also has A antigen and hence blood group A would not be considered as foreign.