Which of the following blood group phenotypes is universally recognized as the universal recipient in human blood transfusions because individuals possessing it have neither anti-A nor anti-B antibodies in their blood plasma?

💡 Solution & Explanation

Individuals with blood group AB positive express both A and B antigens on their red blood cells and lack both anti-A and anti-B antibodies in their plasma, allowing them to receive red blood cells from any ABO blood group. Blood group O negative represents the universal donor because red blood cells lack A, B, and Rh antigens. Presence of antibodies in recipient plasma causes agglutination if mismatched donor cells are introduced. Karl Landsteiner discovered the ABO blood group system.