$\begin{array}{1 1} (a)\;\text{bone like substance covering the root of a tooth } \\ (b)\; \text{substance between enamel or cementum and the pulp chamber} \\ (c)\; \text{the central part of the tooth filled with soft connective tissue} \\ (d)\; \text{is the hardest and most highly mineralized substance of the body} \end{array}$
