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: Medicine
Biopsy in PAN shows: 
Select and explain. 
A. Necrotizing aeritis, B. Atrophy, C. Granulomatous lesion, D. Ring lesion
A: Necrotizing aeritis
Answer: A: Necrotizing aeritis 
Explanation: Answer is A (Necrotizing aeritis): PAN is characterized by necrotizing vasculitis of small and medium sized muscular aeries. The vascular lesion in PAN is necrotizing inflammation of small and medium sized muscular aeries.