AB+ is the universal recipient.

AB+ is the universal recipient.

• A. Universal donor
• B. AB+
• C. Universal recipient
• D. Rare

Answer: (B)

The key idea here is transfusion compatibility based on ABO and Rh factors. AB positive individuals have both A and B antigens on their red blood cells and, in their plasma, no anti-A or anti-B antibodies. That means they won’t attack transfused blood that has A or B antigens, no matter which ABO type it comes from. The Rh part matters too: AB positive has the D antigen, so they can receive blood that is either Rh positive or Rh negative without mounting an anti-D reaction. Put together, AB positive can receive red blood cells from any ABO type and any Rh type, which is why they’re known as universal recipients. For contrast, universal donors refer to those whose blood can be given to any recipient—in red blood cell transfusions, that’s O negative, since it lacks A, B, and D antigens. The option “rare” isn’t a defining feature of transfusion compatibility.

The key idea here is transfusion compatibility based on ABO and Rh factors. AB positive individuals have both A and B antigens on their red blood cells and, in their plasma, no anti-A or anti-B antibodies. That means they won’t attack transfused blood that has A or B antigens, no matter which ABO type it comes from. The Rh part matters too: AB positive has the D antigen, so they can receive blood that is either Rh positive or Rh negative without mounting an anti-D reaction. Put together, AB positive can receive red blood cells from any ABO type and any Rh type, which is why they’re known as universal recipients.

For contrast, universal donors refer to those whose blood can be given to any recipient—in red blood cell transfusions, that’s O negative, since it lacks A, B, and D antigens. The option “rare” isn’t a defining feature of transfusion compatibility.