Test2-64. 

The majority of scientists believe that to reduce and stabilize atmospheric concentrations of carbon dioxide, emissions must be cut at the source by fossil fuels that are burned more efficiently and, in some cases, by alternatives such as hydrogen fuel cells that can replace fossil fuels altogether.

(A) fossil fuels that are burned more efficiently and, in some cases, by alternatives such as hydrogen fuel cells that can replace fossil fuels altogether

(B) fossil fuels that are burned more efficiently and, in some cases, those that are replaced altogether with alternatives such as hydrogen fuel cells

(C) burning fossil fuels more efficiently and, in some cases, by replacing fossil fuels altogether with alternatives such as hydrogen fuel cells

(D) more efficiency in the burning of fossil fuels and, in some cases, by alternatives such as hydrogen fuel cells that can replace fossil fuels altogether

(E) the more efficient burning of fossil fuels and, in some cases, by fossil fuels that are replaced altogether with alternatives such as hydrogen fuel cells

AnsC)

為什麼我覺得(A)比較好呀?
emissions must be cut at the source by burning fossil fuels more efficiently and, in some cases, by replacing fossil fuels altogether with alternatives such as hydrogen fuel cells

emissions可以做burn和replace這兩個動作嗎?
如果主詞是people之類的話才可以選(A)吧?

emissionvs   must be cut

that is a total sentance

而且这句话的正常语序是　burning fossil fuels and　replacing fossil fuels 是用来　cut　emission的

楼主估计看太多语法有点晕了吧，　这句话本来就和后面的用来做修饰的方法是没有关系，他们不需要主语一致的，而且，这句话是被动语态啊．

the apple was cut by using the knife(by me ),被动语态中　施动的真正主语可以省略的呀．