Choose the correct option for following statements : 

(I) $s{p}^3$ hybrid orbitals are at $90°$ to one another 

(II) $s{p}^3{d}^2$ adjacent hybrid orbitals are at $90°$ to one another 

(III) $s{p}^2$ hybrid orbitals are at $120°$ to one another 

(IV) Bond order of $N–O$ bond in $N{O}_3^{-}$ is $1\raisebox{1ex}{$1$}\!\left/ \!\raisebox{-1ex}{$3$}\right.$