Zinc can be coated on iron to produce galvanized iron but the reverse is not possible. It is because
(1) Zinc is lighter than iron
(2) Zinc has lower melting point than iron
(3) Zinc has lower negative electrode potential than iron
(4) Zinc has higher negative electrode potential than iron

Correct option
(d) zinc has higher negative electrode potential than iron
Explanation:
Reduction potential values of
( E_{mathrm{Zn}^{2+} / mathrm{Zn}}^{circ}=-0.76 mathrm{V} ) and
( E_{mathrm{Fe}^{2+} / mathrm{Fe}}^{circ}=-0.44 mathrm{V} )
Thus, due to higher negative electrode potential value of zinc than iron, iron cannot be coated on zinc.