The correct statement is:
Zincite is a carbonate ore
Aniline is a froth stabilizer
Zone refining process is used for the refining of titanium
Sodium cyanide cannot be used in the metallurgy of silver

The ore contains rocky impurities which are needed to be separated before processing. This process is called the concentration of ore. The principle of the froth flotation process is that sulphide ores are preferentially wetted by the pine oil, whereas the gangue particles are wetted by the water. In this process, a suspension of a powdered ore is made with water. In this process, a suspension of a powdered ore is made with water.Collectors like pine oil, fatty acids and xanthates are added to it. Froth stabilizers like cresols, aniline stabilize the froth. The minerals particles become wet by oils while gangue particles by water. The mixture is agitated with the help of mechanical stirrer by passing blast of air. The froth is formed which is lighter and skimmed off. The froth is dried for recovery of the ore particles.Hence, the correct option isC