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': 'A typical gingivitis is \nSelect and explain. \nA. other name of plasma cell gingivitis, B. gingivitis seen in HIV patients, C. gingivitis seen in leukaemia patients, D. gingivitis seen in aggressive periodontitis', 'role': 'user'}, {'content': 'Answer: A \nExplanation: None', 'role': 'assistant'}]