Name the autoimmune disease of body muscles.

Explanation

**Step-by-Step Solution:**

1. **Understanding Autoimmune Diseases**: Autoimmune diseases occur when the immune system mistakenly attacks the body’s own cells. Normally, the immune system protects the body against foreign invaders like pathogens (bacteria, viruses, etc.). However, in autoimmune disorders, the immune system fails to recognize self-cells and produces antibodies against them.

2. **Identifying the Affected Area**: The question specifically asks for an autoimmune disease that affects body muscles. This indicates that we need to look for a condition where the immune response targets muscle cells.

3. **Researching Autoimmune Disorders of Muscles**: Among various autoimmune diseases, some are known to affect muscle function. One prominent example is Myasthenia Gravis. This condition is characterized by weakness and rapid fatigue of the voluntary muscles.

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