Classical monoblock in restorative and endodontic literature is:: (A) Primary monoblock, (B) Secondary monoblock, (C) Tertiary monoblock, (D) Quartenary monoblock
Answer is B. 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. 
Secondary monoblocks are those that have two circumferential interfaces, one between the cement and dentin, the other between the cement and the core material. 
A secondary monoblock is the type of monoblock that is classically perceived in the restorative and endodontic literature.