Sentence Correction

The Environmental Protection Agency's proposal to place restrictions on both diesel fuel and diesel engines has sparked a counterattack by the oil industry, saying that the move will exacerbate the nation's fuel supply problems.


IMO C

the subject of the preceding clause should be modified by "saying"...
So in original sentence it seems as Proposal is saying something..

Instead we mean Oil industries are saying something...this is presented
well in option C

A. on both diesel fuel and diesel engines has sparked a counterattack by the oil industry, saying

C. on both diesel fuel and diesel engines has sparked a counterattack by the oil industry, which says