Which is not an autoimmune disease

Options

A. Grave's disease
B. Pernicious anaemia
C. Rheumatoid arthritis
D. Insomnia

Answer

To determine which condition is not an autoimmune disease, we can follow these steps:

### Step-by-Step Solution:

1. **Understand Autoimmune Diseases**:
- Autoimmune diseases occur when the immune system mistakenly attacks the body's own cells, mistaking them for foreign invaders. This can lead to damage and various health issues.

2. **Identify Examples of Autoimmune Diseases**:
- Common examples include:
- Type 1 Diabetes
- Graves' Disease
- Pernicious Anemia
- Rheumatoid Arthritis
- These conditions involve the immune system targeting the body’s own tissues.

3. **Analyze the Given Options**:
- The question presents several conditions, and we need to identify which one is not classified as an autoimmune disease.

4. **Evaluate Each Option**:
- **Graves' Disease**: An autoimmune disorder affecting the thyroid.
- **Pernicious Anemia**: An autoimmune condition that affects the absorption of vitamin B12.
- **Rheumatoid Arthritis**: An autoimmune disease that causes joint inflammation.
- **Insomnia**: A sleep disorder characterized by difficulty falling or staying asleep, which does not involve the immune system attacking the body.

5. **Conclusion**:
- After evaluating the options, it is clear that **Insomnia** is not an autoimmune disease. Therefore, the answer is **option number 4**.

### Final Answer:
**Insomnia is not an autoimmune disease.**

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