Which of the following represents Magnification ‘m’ of spherical mirror?

i) $\raisebox{1ex}{$v$}\!\left/ \!\raisebox{-1ex}{$u$}\right.$    ii) $-\raisebox{1ex}{$v$}\!\left/ \!\raisebox{-1ex}{$u$}\right.$    iii) $\raisebox{1ex}{$h_i$}\!\left/ \!\raisebox{-1ex}{$h_o$}\right.$   iv) $\raisebox{1ex}{$h_o$}\!\left/ \!\raisebox{-1ex}{$h_i$}\right.$