$\begin {array} {1 1} (A)\;\text{Borax involves two boron atoms in $ sp^2$ hybridization and two boron atoms in $sp$ hybridization} \\ (B)\;\text{Borax involves two boron atoms in $ sp^2$ hybridization and two boron atoms in $sp^3$ hybridization} \\ (C)\;\text{Borax involves all the four atoms in $ sp^2$ hybridization } \\ (D)\;\text{Borax involves all the four atoms in $ sp^3$ hybridization } \end {array}$
