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
[{'content': 'Arthus reaction is what type of hypersensitivity reaction \nSelect and explain. \nA. Localized immune complex, B. Ag-Ab reaction, C. Complement mediated, D. Ab mediated', 'role': 'user'}, {'content': 'Answer: A \nExplanation: The Arthus reaction is a localized area of tissue necrosis resulting from acute immune complex vasculitis, usually elicited in the skin. Revise the mnemonics “SHARP“ from the text.', 'role': 'assistant'}]