______ is the first immunoglobulin class produced during a primary response.

• A. IgA.
• B. IgE.
• C. IgM.
• D. IgG.

Answer: (C)

Verified step by step guidance

1. Understand the context: The problem is asking about the first immunoglobulin class produced during a primary immune response.
2. Recall the function of immunoglobulins: Immunoglobulins, or antibodies, are proteins produced by B cells that play a crucial role in the immune response by identifying and neutralizing pathogens like bacteria and viruses.
3. Identify the immunoglobulin classes: The main classes of immunoglobulins are IgA, IgD, IgE, IgG, and IgM, each with distinct roles in the immune system.
4. Focus on primary immune response: During a primary immune response, the body encounters a pathogen for the first time, and the immune system responds by producing antibodies.
5. Recognize the role of IgM: IgM is the first antibody to be produced in response to an initial exposure to an antigen, making it the primary immunoglobulin class during a primary immune response.