Consider the following statements,
I. Sc has a low value of ${\mathrm{E}}_{{\mathrm{M}}^{+3}/{\mathrm{M}}^{+2}}^0$
II. Zn has the highest value of ${\mathrm{E}}_{{\mathrm{M}}^{+3}/{\mathrm{M}}^{+2}}^0$
III.Mn and Fe have comparatively high and low values of ${\mathrm{E}}_{{\mathrm{M}}^{+3}/{\mathrm{M}}^{+2}}^0$ respectively.

Sc is not stable with +2 oxidation state, hence reduction potential is low

Zn is more stable with +2 oxidation state,hence highest reduction potential

Mn with +2 is more stable than Fe with +2,hence Mn has high value whereas Fe will be low comparitively