How is leaching carried out in case of low grade copper ores?

Options

A. Leaching is carried out with NaOH and `O_(2)`
B. Leaching is carried out with NaCN.
C. Leaching is carried out with acids in presence of `H_(2)`.
D. Leaching is carried out by boiling the ore with water.

Answer

C

Explanation

Leaching of low grade copper ores is carried out with acid or bacteria , when copper goes into solution as `Cu^(2+)` ions.
`Cu_((aq))^(2+) + H_(2(g)) to Cu_((s)) + 2H_((aq))^(+)`