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: Dental
[{'content': 'Following is a type of physical urticaria – \nSelect and explain. \nA. Dermographism, B. Urticaria pigmenthosa, C. Urticaria vasculitis, D. Auto-immune urticaria', 'role': 'user'}, {'content': 'Answer: A \nExplanation: None', 'role': 'assistant'}]