Question

When red blood corpuscles containing both A and B antigens are mixed with your blood serum, they agglutinate. Hence your blood group is
A. A
B. B
C. AB
D. O

Answer 1

Let us first look into the antigens and blood corpuscles. An antigen is a foreign substance that can cause the production of antibodies by the immune system to fight against it. An antigen can be any substance that is present in the environment like air, chemical. Blood corpuscles are commonly called blood cells that function as transport of nutrients to hormones throughout the body.

Complete answer:
A person with blood group O does not contain any antigen but contains both anti- A and anti- B antibodies.
Therefore when the blood with both A and B antigens are mixed with the blood type and it causes agglutination, it is the O type because the O type has both antibodies which will cause clumping with antigens A and B.
That is the reason why a person with blood group O cannot receive blood from any other blood type other than O blood group
The people who hold the type O blood, their red blood cells, have neither A or B markers. Therefore that person’s body will have both A and B antibodies and will therefore feel the need to defend itself against A, B, and AB blood.

Therefore the correct answer is 'O' for the above question.

Note: The blood group antigens are actually either sugars or proteins, and they are attached to various components in the red blood cell membrane.
Considering an example, the antigens of the ABO blood group are sugars. These sugars are produced by some series of reactions by which enzyme catalysis and transfer the sugar units.
The person with O blood can only get a transfusion with O blood.