T he correct statement(s) related to the metal extraction processes is(are)

A

A mixture of PbS and PbO undergoes self-reduction to produce Pb and $$SO_2$$.

B

In the extraction process of copper from copper pyrites, silica is added to produce copper silicate.

C

Partial oxidation of sulphide ore of copper by roasting, followed by self-reduction produces blister copper.

D

In cyanide process, zinc powder is utilized to precipitate gold from $$Na[Au(CN)_2]$$.