Which of the following is an autoimmune disorder?

Options

A. Parkinson's disease
B. Myasthenia gravis
C. AIDS
D. SCID

Answer

To determine which of the following is an autoimmune disorder, we need to analyze the options provided. Autoimmune disorders occur when the immune system mistakenly attacks healthy cells in the body. Here’s a step-by-step breakdown:

1. **Understand Autoimmune Disorders**: Autoimmune disorders are conditions where the immune system attacks the body’s own tissues. Examples include diseases like rheumatoid arthritis, lupus, and myasthenia gravis.

2. **Evaluate the Options**:
- **Option 1: Parkinson's Disease**: This is a neurological disorder characterized by the degeneration of nerve cells in the brain, particularly those that produce dopamine. It is not caused by an autoimmune response, so it is not an autoimmune disorder.
- **Option 2: Myasthenia Gravis**: This is indeed an autoimmune disorder where the immune system attacks the communication between nerves and muscles, leading to muscle weakness. This matches the definition of an autoimmune disorder.
- **Option 3: AIDS**: Acquired Immunodeficiency Syndrome (AIDS) is caused by the Human Immunodeficiency Virus (HIV) and is not classified as an autoimmune disorder. It is an infectious disease.
- **Option 4: SCID (Severe Combined Immunodeficiency)**: This is a genetic disorder that results in a severely compromised immune system. It is classified as an immunodeficiency disorder, not an autoimmune disorder.

3. **Conclusion**: After evaluating all the options, the only condition that fits the definition of an autoimmune disorder is Myasthenia Gravis.

**Final Answer**: The correct answer is **Option 2: Myasthenia Gravis**.

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