Deduce from the following E° values of half cells, what combination of two half cells would result in a cell with the largest potential?

I)   $\mathrm{A}\to {\mathrm{A}}^{+}+\mathrm{e}$ ;    E° = –0.24V

II)  ${\mathrm{B}}^{-}\to \mathrm{B}+\mathrm{e}$ ;    E° = –2.1V

III) $\mathrm{C}\to {\mathrm{C}}^{2+}+2\mathrm{e}$ ;    E° = –0.38V

IV) ${\mathrm{D}}^{2-}\to {\mathrm{D}}^{-}+\mathrm{e}$ ;    E° = –0.59V

• A

  I and IV

• B

  II and III

• C

  III and IV

• D

  I and II