# The Impurities present in bauxite are

$(a)\;\text{Sulphur, Silicone and Phosphorous.} \\(b)\;\text{Sulphur, Arsenic, and Phosphorous.} \\(c)\; \text{$SiO_2$, iron oxide and titanium oxide.} \\ (d)\;\text{$SiO_2$, zinc oxide and titanium oxide.}$

The principal ore of aluminium, bauxite, usually contains $SiO_2$, iron oxide and titanium oxide as impurities.
The major impurities in Bauxite are iron oxides (goethite & hematite), silicon dioxide, the clay mineral kaolinite as well as small amounts of anatase ($TiO_2$).
Concentration is carried out by digesting the powdered ore with a concentrated solution $NaOH$ at $473 - 523\; K.$
Hence c is the correct answer.
edited Mar 24