Which one of the following alio tropes of carbon is isomorphous with crystalline silicon?

Diamond is the allotrope of carbon that is isomorphous with crystalline silicon. Both substances share the same 'diamond cubic' crystal structure, where each atom is tetrahedrally bonded to four neighboring atoms. In diamond, each carbon atom is sp3 hybridized and linked to four other carbon atoms via strong sigma bonds, creating a rigid three-dimensional network. Similarly, crystalline silicon, which belongs to the same group (Group 14) as carbon, adopts this diamond-like structure under ambient conditions. While graphite consists of two-dimensional layers of sp2 hybridized atoms, and amorphous forms like coke and coal lack a defined crystalline lattice, diamond and silicon are isostructural. This structural similarity is a result of their shared valency and preference for tetrahedral coordination in their most stable crystalline forms [1].

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1. [1] https://www.sciencedirect.com/science/article/abs/pii/S0022369719319328