With respect to graphite and diamond, which of the statement(s) given below is(are) correct?

(A) Diamond is harder than graphite (B) In graphite, each carbon atom is joined to three other C atoms leaving one free valence which results in electrical conductance. In diamond, all four valencies of carbon are satisfied due to which diamond is an insulator. Thus, graphite has higher electrical conductivity than diamond (C) Diamond has higher thermal conductivity than graphite due to the transfer of thermal vibrations from atom to atom. Diamond has a compact and precisely aligned crystal which helps in the fast movement of heat (D) Graphite has a higher C−C bond order than diamond. Graphite contains C=C double bond whereas diamond contains C−C single bond only. Hence, the correct options are B and D.