Colloid of which one of the following can be prepared by electrical dispersion as well as reduction method?

Colloid of which one of the following can be prepared by electrical di

1.	Colloid of which one of the following can be prepared by electrical dispersion as well as reduction method?
Answer» Sulphur Ferric hydroxide Arsenious sulphide Gold. Solution :Gold COLLOID can be prepared by BREDIG arc method as WELL as by reduction of `AuCl_(3)` with `SnCl_(2)`