Question

Conversion of antigen to harmless insoluble matter by antibody is

• A. Neutralisation
• B. Opsonization
• C. Activation
• D. Agglutination

Answer 1

The correct option is D Agglutination

• Agglutination is the process that occurs if an antigen is mixed with its corresponding antibody called isoagglutinin.
  
• The clumping of cells such as bacteria or red blood cells takes place in the presence of an antibody or complement. The antibody or other molecule binds multiple particles and joins them, creating a large complex.
• This increases the efficacy of microbial elimination by phagocytosis as large clumps of bacteria can be eliminated in one pass, versus the elimination of single microbial antigens.
  

So, the correct answer is 'Agglutination'