Blood Compatibility for Group A Recipients

Steps:

• Recipient A has anti-B antibodies, so donor RBCs must lack B antigens to avoid agglutination.
• Group A donor has only A antigens, no B, so safe.
• Group O donor has no A or B antigens, universally compatible as donor.
• Group B has B antigens, incompatible.
• Group AB has B antigens, incompatible.

Why B is correct:

• Groups A and O both lack B antigens, preventing reaction with recipient A's anti-B antibodies per ABO compatibility rules.

Why the others are wrong:

• A: AB has B antigens, triggering anti-B attack.
• C: B has B antigens, directly attacked by anti-B.
• D: Omits group A, which is fully compatible.

Final answer: B