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
Where is onion bulb appearance on nerve biopsy seen in? 
Select and explain. 
A. Amyloid neuropathy, B. Diabetic neuropathy, C. CIDP, D. Leprous neutitis
C: CIDP
Answer: C: CIDP 
Explanation: . CIDP