The correct option is D To neutralise the charges on the surface
Electroplating involves coating the layer of a metal on another metal via electrolysis. Gold and silver are electroplated over artifical jewels to make them appear shiny, Zinc is usually electroplated over iron to prevent corrosion of iron. Tin is electroplated over steel in cans so as to prevent the reaction between iron and the food inside the can.
However, neutralising charges on the surface doesn't need electroplating.