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
Hypersensitivity vasculitis involves - 
Select and explain. 
A. Capillary, B. Arterioles, C. Postcapillary venules, D. Medium sized arteries
C: Postcapillary venules
Answer: C: Postcapillary venules 
Explanation: None