关于平行的定语从句第二个that需不需要省略的问题

bonbonjon

题目是OG 13 85，答案是E没错，比较疑惑的是D选项。可以看到and后面没有平行地补出that，所以想请教NN们，平行定语从句的第二个that是不是一定要保留呢？

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

别贝尔

that是否省略主要看平行是否正确。
D选项 dioxins that currently uncontrolled and  North Americans are exposed to come that修饰句（我个人成为sub clause）与Clause（subject+verb）
and后面是完成的clause与前面的sub clause不能平行

OG16 128题（楼主可以看下OG13中有没）
Scientists have recently found evidence that black holes —— (对black holes解释）——probably exist at the core of nearly all galaxies and the mass of each black hole is proportional to its host galaxy.
这里and后面的clause不予that句平行，而是与clause Scientists have [size=14.0000009536743px] [size=14.0000009536743px]recently found evidence平行，所以省略that错误，因为原句意思为描述evidence 证明了的两件事。
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此外！这里还有一个错误就是modifier不能以介词结尾
所以C也错误， dioxins that NA are exposed to 错误，应该改为正确答案那样
the restaurant that we ate at  →  the restaruant at which we ate
the person I spoke with → the person with whom I spoke