copper(I) sulphide
carbon monoxide
sulphur dioxide
iron(II) sulphide
The correct option is A copper(I) sulphide
In the extraction of copper from its sulphide ore, the metal is finally obtained by the reduction of cuprous oxide with copper(I) sulphide.
2Cu₂S + 3O₂ → 2Cu₂O + 2SO₂
2Cu₂O + Cu₂S → 6Cu + SO₂