The correct answer is option 4: Any blood group. A person with blood group AB is considered a universal recipient. This means that they can receive blood from any other blood group, including A, B, AB, and O. The reason for this is that individuals with blood group AB have both A and B antigens present on the surface of their red blood cells. Since they have both antigens, their immune system does not produce antibodies against either antigen. As a result, they can safely receive blood from donors with different blood types without their immune system attacking the transfused red blood cells. It is important to note that while individuals with blood group AB can receive blood from any group, they can only donate to individuals with blood group AB.