Answer:
The correct answer is c. IgM
Step-by-step explanation:
IgM is the first class of antibody which is produced by the body during primary response to antigen. IgM is the largest antibody and is present on the surface of B lymphocytes.
It controls the activation of B-cell and is released by B cell in the circulation to provide first line of defense to the body against any infection. It is a pentameric antibody found in the blood and due to pentameric in nature it has high avidity for antigen binding and processing.
It is responsible for agglutination reaction and protect us from viral and bacterial infection. It consists about 5-10% of total antibodies present in the body.