Which antibody titer rises during allergy ?

Options

A. Immunoglobulin A
B. Immunoglobulin G
C. Immunoglobulin M
D. Immunoglobulin E

Answer

To solve the question "Which antibody titer rises during allergy?", we can follow these steps:

### Step-by-Step Solution:

1. **Understand the Context of Allergies**: Allergies are immune responses to substances that are typically harmless, such as pollen, dust, or certain foods. The immune system reacts by producing specific antibodies.

2. **Identify the Types of Antibodies**: The question provides four options:
- Immunoglobulin A (IgA)
- Immunoglobulin G (IgG)
- Immunoglobulin M (IgM)
- Immunoglobulin E (IgE)

3. **Analyze Each Antibody**:
- **Immunoglobulin A (IgA)**: This antibody is primarily found in mucosal areas, such as the respiratory and gastrointestinal tracts, and is not specifically associated with allergic reactions.
- **Immunoglobulin G (IgG)**: This is the most abundant antibody in the blood and is involved in the body's response to infections, but it does not specifically rise during allergic reactions.
- **Immunoglobulin M (IgM)**: This antibody is the first to respond to infections but is not specifically linked to allergies.
- **Immunoglobulin E (IgE)**: This antibody is present in very low amounts in the blood but increases significantly during allergic reactions. It plays a crucial role in the body's response to allergens.

4. **Conclusion**: Based on the analysis, the antibody that rises during an allergic reaction is **Immunoglobulin E (IgE)**.

### Final Answer:
The antibody titer that rises during allergy is **Immunoglobulin E (IgE)**.

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