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 exposedcomes
==> Usage of "Much" is incorrect here. Dioxins is plural and hence will need plural "Many" instead of "much"
(B)much of the currently uncontrolled dioxins that North Americans
...
(A)much of the currently uncontrolled dioxins to which North Americans are exposedcomes
==> Usage of "Much" is incorrect here. Dioxins is plural and hence will need plural "Many" instead of "much"
(B)much of the currently uncontrolled dioxins that North Americans
...
