OG-34求助

34. A report by the laceName w:st="on">AmericanlaceName> laceType w:st="on">AcademylaceType> for the Advance­ment of Science has concluded that much of the currently uncontrolled dioxins to which North Ameri­cans are exposed comes from the incineration of wastes.

(A)  much of the currently uncontrolled dioxins to which North Americans are exposed comes

(B)  much of the currently uncontrolled dioxins that North Americans are exposed to come

(C)  much of the dioxins that are currently uncon­trolled and that North Americans are exposed to comes

(D)  many of the dioxins that are currently uncontrolled and North Americans are exposed to come

(E)  many of the currently uncontrolled dioxins to[Y1]  which North Americans are exposed come

Choices A, B, and C are flawed because the countable noun dioxins should be modified by many rather than much, which is used with uncountable nouns such as "work" and "happi­ness." In addition, both A and C incorrectly use the singular verb comes with the plural noun dioxins. Choices C and D are needlessly wordy, and D requires that before North Americans, to be grammatically complete. Choice E, the best answer, is both grammatically correct and concise.

which North Americans are exposed to

把介词to放在which前面了。定语从句修饰dioxins.