A universal recipient of blood belongs to blood group?

Step 1: Analyze the question The question asks which blood group is the universal recipient, meaning the group that can receive blood from all other groups (A, B, AB and O) without a reaction.

Step 2: Explain the concept Blood groups are decided by the antigens on the surface of red blood cells and the antibodies in the plasma:

| Blood group | Antigens on red cells | Antibodies in plasma | |---|---|---| | A | A | anti-B | | B | B | anti-A | | AB | A and B | none | | O | none | anti-A and anti-B |

A transfusion reaction happens when the recipient's plasma antibodies attack the donor's red cell antigens.

Step 3: Apply it

• Group AB has both A and B antigens but no anti-A or anti-B antibodies.
• So AB plasma has nothing to attack donor cells of A, B, AB or O.
• Therefore, AB can safely receive blood from every group. It is the universal recipient.

By contrast:

• Group O has no antigens, so its red cells are not attacked by anyone. It is the universal donor.
• Groups A and B can receive only from their own group and from O.

Step 4: Answer The universal recipient is AB, which is option B.

Exam tip: Remember "AB = All Blood can be received" and "O = Only gives to all" (universal donor, since it has "zero" antigens). JAMB often asks both versions, so do not mix them up!