Graphite is best described as which type of crystalline solid?
a) A molecular solid composed of discrete C6 graphene fragments held together only by London dispersion forces.
b) A covalent network solid consisting of a three-dimensional framework of σ bonds between all carbon atoms.
c) A covalent network solid in which each carbon atom is covalently bonded within two–dimensional layers that are held together by London dispersion forces.
d) A metallic solid consisting of carbon atoms immersed in a sea of delocalized valence electrons.