This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: None, Subject name: Pathology
Target fibres are characteristically seen in a muscle biopsy of - 
Select and explain. 
A. Dermatomyositis, B. Motor neuron disease, C. Myasthenia gravis, D. Drug induced myopathy
B: Motor neuron disease
Answer: B: Motor neuron disease 
Explanation: Target fibers

During denervation atrophy there is a cytoskeletal reorganization of some muscle cells, which results in a rounded zone of disorganized filaments in the centre of the fiber (target fiber).
Amongst the given options only motor neuron disease can result in denervation of the muscle.