A report by the American Academy 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 which North Americans are exposed come
We cannot say "much of the dioxins", because DIOXINS is the plural of DIOXIN and hence countable.
---> eliminate A, B, C
Reason to eliminate D:
D contains an AND, so we must check parallelism.
After the AND: "North Americans are exposed to"
Before the AND: nothing parallel to "North Americans are exposed to"
"Not parallel" is a good, solid reason to eliminate D.
E has no problem
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