Which blood type has A antigens and anti-B antibodies?

• A. Type A
• B. Type AB
• C. Type B
• D. Type O

Answer: (A)

In the ABO system, red blood cells carry specific surface antigens (A or B or both or neither), and the plasma contains antibodies against the antigens you don’t have. The type with A antigens on the red cells and anti-B antibodies in the plasma matches this description. So this blood type has A antigens and anti-B antibodies.

For context, type AB would have both A and B antigens and no anti-A or anti-B antibodies; type B would have B antigens and anti-A antibodies; type O would have no A or B antigens and both anti-A and anti-B antibodies.