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': 'Classical monoblock in restorative and endodontic literature is: \nSelect and explain. \nA. Primary monoblock, B. Secondary monoblock, C. Tertiary monoblock, D. Quartenary monoblock', 'role': 'user'}, {'content': 'Answer: B \nExplanation: The combined use of a core material and a cement/sealer in contemporary endodontic obturations and fiber post adhesion introduces additional interfaces into a monoblock.\xa0\nSecondary monoblocks are those that have two circumferential interfaces, one between the cement and dentin, the other between the cement and the core material.\xa0\nA secondary monoblock is the type of monoblock that is classically perceived in the restorative and endodontic literature.', 'role': 'assistant'}]