This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Vasculitis, Subject name: Medicine
Which of the following is an example of small vessels vasculitis? 
Select and explain. 
A. Takayasu aeritis, B. Microscopic polyangitis, C. Giant cell aeritis, D. Polyaeritis nodosa
B: Microscopic polyangitis
Answer: B: Microscopic polyangitis 
Explanation: Microscopic polyangitis affects capillaries venules and aerioles besides affecting pulmonary vessels In contrast pulmonary vessels are not involved in polyaeritis nodosa. Takayasu effects aoa and its major branches. Giant cell aeritis affects cranial vessels most commonly temporal aery.