When burnt in air, a 12.0 g mixture of carbon and sulphur yields a mixture of `CO_2` and `SO_2` , in which the number of moles of `SO_2` is half that of `CO_2`.The mass of the carbon the mixture contains is : (At . Wt. S=32)
A. 0.75
B. 0.5
C. 0.4
D. 0.25