This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Myasthenia Gravis and Muscular dystrophy, Subject name: Medicine
All of following are examples of proximal muscle weakness EXCEPT? 
Select and explain. 
A. Myasthenia gravis, B. Thyroid myopathy, C. Myotonic dystrophy, D. Duchenne's muscular dystrophy
C: Myotonic dystrophy
Answer: C: Myotonic dystrophy 
Explanation: Myasthenia gravis Features Eye muscle weakness, Ptosis, Diplopia In contrast, all myopathies have a proximal weakness (an exception being Myotonic dystrophy, which has a distal weakness).