To which group blood can be donated by a person from blood group A?

A person from blood group A can only donate blood to a persons of blood group A and AB. This so because blood group B and O have antibodies against A antigen (anti-A) and if they are transfused with A blood group would react destroying the transfused red blood cells. Blood group A and AB lack antibodies against A antigen and hence if transfused with blood group A they wound be compatible produsing no transfusion reaction.

Blood type A can donate to blood types A and AB