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: Pathology
All is true about Giant cell aeritis except: 
Select and explain. 
A. Involves large to medium sized aeries, B. Granulomatous inflammation, C. Most commonly involved aery is abdominal aoa, D. Segmental nature of the involvement
C: Most commonly involved aery is abdominal aoa
Answer: C: Most commonly involved aery is abdominal aoa 
Explanation: It is the most common type of vasculitis in adults (usually >50 years) This vasculitis is characterized by granulomatous aeritis of the aoa and its major branches paicularly the extracranial branches of the carotid aery. Since the superficial temporal aery is the most commonly involved vessel, the giant cell aeritis is called as temporal aeritis. Clinical features include constitutional symptoms like fever, fatigue, weight loss, jaw pain facial pain, localized headache (most intense along the anatomical course of the superficial temporal aery) and sudden onset of blindness (due to involvement of ophthalmic aery). Biopsy of temporal aery is the investigation of choice. Microscopically, there is presence of granulomatous inflammation with multinucleated giant cells and fragmentation of internal elastic lamina.