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: Microbiology
[{'content': 'The distinguishing characteristic of a positive delayed-type hypersensitivity skin test is \nSelect and explain. \nA. Erythema, B. Necrosis, C. Induration, D. Vasculitis', 'role': 'user'}, {'content': 'Answer: C \nExplanation: None', 'role': 'assistant'}]