Which is not correct statement ?
(A) Casseterite, chromite and haematite are concentrated by hydraulic washing (Tabling).
(B) Pure Al2O3 is obtained from the bauxite ore by leaching in the Bayer's process.
(C) Sulphide ore is concentrated by calcination method.
(D) Roasting can convert sulphide into oxide or sulphate and part of sulphide may also act as a reducing agent.