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': 'Immediate implant placement in extraction socket can be indicated in? \nSelect and explain. \nA. Periodontal bone loss, B. Suppuration, C. Cellulitis, D. Lack of bone apical to socket', 'role': 'user'}, {'content': 'Answer: A \nExplanation: Indications and contraindications of immediate implant placement in extraction socket according to Block & Kent:-', 'role': 'assistant'}]