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 most important aspect of emergency treatment for\nan acute apical abscess is to: \nSelect and explain. \nA. Produce sedation, B. Obturation, C. Establish drainage, D. None of the above', 'role': 'user'}, {'content': 'Answer: C \nExplanation: None', 'role': 'assistant'}]