A.
CU + 2H2SO4 CUSO4 + SO2 + 2H2O
B.
3S + 2H2SO4 3SO2 + 2H2O
C.
C + 2H2SO4 CO2 + 2SO2 + 2H2O
D.
CAF2 + H2SO4 CASO4 + 2HF
Option D ,
here the oxidation state of S does not increase it remains same.
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