Question

Assertion :Type ${}^{\prime }{O}^{\prime }$ blood group individuals are called 'universal donors'.
Reason :$RBCs$ of ${}^{\prime }{O}^{\prime }$ blood group have both ${}^{\prime }{A}^{\prime }$ and ${}^{\prime }{B}^{\prime }$ surface antigens.

• A. If both assertion and reason are true and reason is the correct explanation of assertion
• B. If both assertion and reason are true but reason is not the correct explanation of assertion
• C. If assertion is true but reason is false
• D. If both assertion and reason are false

Answer 1

Answer: (C)

If a blood transfusion is made between an incompatible donor and recipient, reaction of antigens on the cells and antibodies in the plasma produces clots that clog the capillaries. Type $O$ blood group individuals are without $A$ and $B$ antigens on their $RBCs$, but have antibodies for both these antigens in their plasma. Hence, these can donate blood to anyone.