When antibodies are mixed with their corresponding antigens present on the surface of animal cells, erythrocytes, or bacteria, they cross-link these objects to form visible clumps. This serological reaction is called as agglutination and is very similar to the precipitation reaction. Both reactions are specific because they depend on the specific antibody and antigen pair. Antigens involved in precipitation reaction are much smaller and more soluble than those involved in agglutination making the latter reaction easily detectable. Which of the following options is best suited to make the precipitation reaction more easily detectable?

• A

  Decreasing the affinity of the antibody for the antigen.
• Correct answer
  B

  Attaching soluble antigens to large, inert carriers such as erythrocytes or latex beads.
• C

  Increasing the ionic strength of the reaction solution.
• D

  Performing the experiment at lower temperature such as $4^{\circ} \mathrm{C}$.

Hence, the correct answer is option: 'B'.