The correct answer is (b).
Blood type is a classification of blood based on the presence or absence of inherited antigenic substances on the surface of red blood cells (RBCs). The ABO blood group system is the most important blood group system in human blood transfusion. It is determined by the presence or absence of two antigens, A and B, on the surface of RBCs. There are four main blood types: A, B, AB, and O.
Blood type O is the universal donor because it does not have any A or B antigens on the surface of RBCs. This means that blood type O can be transfused to people with any blood type. However, people with blood type O can only receive blood from other people with blood type O.
Blood type A has the A antigen on the surface of RBCs. Blood type B has the B antigen on the surface of RBCs. Blood type AB has both the A and B antigens on the surface of RBCs.
If a person receives blood that is not compatible with their blood type, their immune system will attack the transfused blood. This can lead to serious complications, including death.
It is important to know your blood type and the blood type of your family members in case of an emergency. You can find out your blood type by donating blood or by having a blood test done at your doctor’s office.