Exaggerated response of the immune system to antigens is

Options

A. Auto immunity
B. Immune deficiency
C. Allergy
D. Hyposensitivity

Answer

**Step-by-Step Solution:**

1. **Understanding the Question**: The question asks for the term that describes an exaggerated response of the immune system to antigens.

2. **Defining Key Terms**:
- "Exaggerated response" refers to a strong or heightened reaction from the immune system.
- "Antigens" are substances that provoke an immune response, often foreign materials like pathogens.

3. **Role of the Immune System**: The immune system is responsible for defending the body against foreign invaders. It typically reacts to antigens to protect the body.

4. **Identifying the Exaggerated Response**: Sometimes, the immune system reacts too strongly to harmless substances (like pollen or dust), leading to symptoms such as sneezing or itching. This strong reaction is termed as "hypersensitivity."

5. **Recognizing Examples of Hypersensitivity**: Allergies are a common example of hypersensitivity. When the immune system overreacts to allergens, it can cause various allergic reactions.

6. **Evaluating Options**:
- **Autoimmunity**: This is when the immune system attacks the body itself, not an exaggerated response to an external antigen.
- **Immune Deficiency**: This refers to a weakened immune response, which is the opposite of an exaggerated response.
- **Allergy**: This is indeed an exaggerated immune response to a harmless substance, fitting the description in the question.
- **Hyposensitivity**: This indicates a low immune response, which does not match the question.

7. **Conclusion**: The correct term for an exaggerated response of the immune system to antigens is "allergy."

**Final Answer**: Allergy

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