Answer:
The correct answer is option - myasthenia gravis.
Explanation:
A systemic autoimmune disorder is not organ-specific these are more generalized as they attack tissues or organs all over the body. Examples of systemic autoimmune diseases are psoriasis, myasthenia gravis, multiple sclerosis, rheumatoid arthritis, many more.
Myasthenia gravis is the systemic autoimmune disease in the given option as in it autoantibodies to act against acetylcholine receptors in the neuromuscular junctions.
Thus, the correct answer is option - myasthenia gravis.