Which one of the following reactions is an example of auto-reduction?

Options

A. `Fe_3O_4 +4C rarr 3Fe +4CO_2`
B. `Cu_2O + C rarr 2Cu + CO`
C. `Cu_2(aq) + Fe(s) rarr Cu(s) + Fe^(2+)(aq)`
D. `Cu_2O + (1/2)Cu_2S rarr 3Cu +(1/2)SO_2`

Answer

D