Read the following four statements regarding disorders of the muscular and skeletal system: (A) Myasthenia gravis is an autoimmune disorder affecting the neuromuscular junction, leading to fatigue, weakening, and paralysis of skeletal muscle. (B) Muscular dystrophy is a progressive degeneration of smooth muscle, mostly due to a genetic disorder. (C) Tetany is characterised by rapid spasms in muscle due to high Ca⁺⁺ i

Step-by-step solution

Statement (A) is correct as myasthenia gravis is an autoimmune disorder that affects the neuromuscular junction of skeletal muscles. Statement (B) is incorrect because muscular dystrophy involves the progressive degeneration of skeletal muscle, not smooth muscle. Statement (C) is incorrect because tetany is caused by low Ca⁺⁺ in body fluid, not high Ca⁺⁺ . Statement (D) is incorrect because gout is caused by the accumulation of uric acid crystals, not urea crystals. Therefore, exactly three statements are incorrect