Immune disease in which body destroys the ill-functioning thyroid is

Options

A. Simmond's disease
B. Cretininsm
C. Hashimoto's disease
D. Myxoedema.

Answer

To answer the question about the immune disease in which the body destroys the ill-functioning thyroid, we can follow these steps:

### Step-by-Step Solution:

1. **Understanding Autoimmune Diseases**:
- Autoimmune diseases occur when the immune system mistakenly attacks the body's own cells. In this case, we are looking for a disease that specifically targets the thyroid gland.

2. **Identifying the Thyroid-Related Diseases**:
- The options provided are Simon's disease, Cretinism, Hashimoto's disease, and Myxedema. We need to analyze each of these to see which one fits the description of an autoimmune disorder affecting the thyroid.

3. **Analyzing Each Option**:
- **Simon's Disease**: This disease involves the destruction of the anterior lobe of the pituitary gland, not the thyroid gland. Therefore, this option is incorrect.
- **Cretinism**: This condition is characterized by retarded mental and physical development due to a deficiency of thyroid hormones. It does not involve the immune system attacking the thyroid, so this option is also incorrect.
- **Hashimoto's Disease**: This is an autoimmune disorder where the immune system attacks the thyroid gland, leading to a decrease in thyroid hormone production (hypothyroidism). This matches the description given in the question.
- **Myxedema**: This condition occurs in adults due to a deficiency of thyroid hormones and is not related to the immune system attacking the thyroid. Thus, this option is incorrect.

4. **Conclusion**:
- Based on the analysis, the correct answer is **Hashimoto's disease**, as it is the autoimmune disease where the body destroys the ill-functioning thyroid.

### Final Answer:
The immune disease in which the body destroys the ill-functioning thyroid is **Hashimoto's disease**.