Question

In ABO blood group testing, which one of the following is INCORRECT

• A. A group – agglutination with anti-A antibodies
• B. B group – agglutination with anti-B antibodies
• C. AB group – no agglutination with either anti-A or anti-B antibodies
• D. O group – no agglutination with either anti-A or anti-B antibodies

Hint:

AB group has both A and B antigens, so it agglutinates with both anti-A and anti-B antibodies, whereas O group has neither antigen.

Answer 1

The Correct Option is C

Step 1: Understanding blood group agglutination. 
In ABO blood group testing, agglutination (clumping) occurs when specific antibodies react with the antigens on red blood cells. 

- A group will agglutinate with anti-A antibodies. 

- B group will agglutinate with anti-B antibodies. 

- AB group will agglutinate with both anti-A and anti-B antibodies, as it contains both A and B antigens. 

- O group will not agglutinate with either anti-A or anti-B antibodies, as it has no A or B antigens. 
 

Step 2: Analyzing the options. 
(A) A group – agglutination with anti-A antibodies: Correct — A group has A antigens and will agglutinate with anti-A antibodies. 
(B) B group – agglutination with anti-B antibodies: Correct — B group has B antigens and will agglutinate with anti-B antibodies. 
(C) AB group – no agglutination with either anti-A or anti-B antibodies: Incorrect — AB group will agglutinate with both anti-A and anti-B antibodies. 
(D) O group – no agglutination with either anti-A or anti-B antibodies: Correct — O group has no A or B antigens, so there is no agglutination. 
 

Step 3: Conclusion. 
The correct answer is (C) AB group – no agglutination with either anti-A or anti-B antibodies.