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': 'To achieve the objectives of vertical condensation, it is necessary to produce: \nSelect and explain. \nA. A cylindrical canal, B. A conical canal, C. A tapering conical canal, D. A straight canal', 'role': 'user'}, {'content': 'Answer: C \nExplanation: The root canal preparation should develop a continuously tapering cone.\xa0This shape mimics the natural canal shape. Funnel-shaped preparation of canal should merge with the access cavity so that instruments will slide into the canal. Thus, the access cavity and root canal preparation should form a continuous channel.\nTextbook of endodontics, 3rd edition\xa0Nisha Garg, Amit Garg', 'role': 'assistant'}]