Antibodies are of which class of proteins

Options

A. Structural
B. Transport
C. Immunoglobulin
D. Enzymatic

Answer

### Step-by-Step Solution:

1. **Understanding Antibodies**: Antibodies are proteins produced by the immune system to identify and neutralize foreign objects like bacteria and viruses.

2. **Identifying Classes of Proteins**: Proteins can be classified into various categories based on their functions, such as:
- Structural proteins (e.g., collagen, keratin)
- Transport proteins (e.g., hemoglobin)
- Enzymatic proteins (e.g., enzymes that catalyze biochemical reactions)
- Immunoglobulins (antibodies)

3. **Recognizing the Role of Antibodies**: Antibodies specifically function in the immune response. They are produced by B lymphocytes and are crucial for identifying and neutralizing pathogens.

4. **Classifying Antibodies**: Given that antibodies play a key role in the immune system, they fall under the category of immunoglobulins. Immunoglobulins are a specific class of proteins that include antibodies.

5. **Conclusion**: Therefore, the correct answer to the question "Antibodies are of which class of proteins?" is **immunoglobulin**.

### Final Answer:
Antibodies are of the class of proteins known as **immunoglobulins**.

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