大全讨论题

16.   Because natural gas is composed mostly of methane, a simple hydrocarbon, vehicles powered by natural gas emit less of certain pollutants than the burning of gasoline or diesel fuel.

(A) less of certain pollutants than the burning of gasoline or diesel fuel

(B) fewer of certain pollutants than burning gasoline or diesel fuel do

(C) less of certain pollutants than gasoline or diesel fuel

(D)  fewer  of certain pollutants than does burning gasoline or diesel fuel（E）

(E) less fewerof certain pollutants than those burning gasoline or diesel fuel

这里的less修饰certain pollutants 吗？怎么不用 fewer 呢？难道 less 也可以修饰可属名词吗？

请教了