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': 'The predominant fibre groups affected in the early lesion of gingivitis are: \nSelect and explain. \nA. Circular and dentogingival, B. Circular and horizontal, C. Circular and alveolar crest, D. Circular and transseptal', 'role': 'user'}, {'content': 'Answer: A \nExplanation: None', 'role': 'assistant'}]