Great analysis so far.

A team of scientists has recently provided evidence of Earth being bombarded daily with as many as 40,000 small comets, vaporizing in the upper atmosphere to fall to Earth as rain.

C is wrong because uses an icomplete idiom "as much as" is the correct one: "as much ?" is not complete

(C) that as much or more than 40,000 small comets daily bombard Earth, vaporizing in the upper atmosphere, and

I am not sure of what meaning issue you are refering to, but "vaporizing" is not ambiguos. It's not correct but it's not ambiguos
"vaporizing" as COMMA +ING modifes the preceding clause and it usually provides additional info/ explains the clause or shows the consequences
usage-of-verb-ing-modifiers-135220.html
It must also make sense with the subject, and here it does not "scientists - vaporizing "

Also it is not parallel to the next verb "fall" : vaporizing in the upper atmosphere, and fall
since both verbs refer to the comets, they must be parallel

I think I'll go with Option E! Great question, thanks. I guess there are very good explanations above me so I'll stick to the same
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Thanks for clarifying! My analysis for meaning issue in option C the sentence is now stating that there could be an equal number or greater number whereas the original sentence states that as many as 40,000 small comets

Another issue with C is much vs many

A team of scientists has recently provided evidence that Earth is bombarded daily with as many as 40,000 small comets that vaporize in the upper atmosphere and fall to Earth as rain.

Answer must be option (E) for the highlighted errors in red.
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A team of scientists has recently provided evidence of Earth being bombarded daily with as many as 40,000 small comets, vaporizing in the upper atmosphere to fall to Earth as rain.
evidence of is wrong. evidence that is correct.

wrong because of the above stated reason.

same as (A)

as much or more than? who writes like this?

unnecessary parallelism. (E) conveys the message way better.

A team of scientists has recently provided evidence of Earth being bombarded daily with as many as 40,000 small comets, vaporizing in the upper atmosphere to fall to Earth as rain.

(A) of Earth being bombarded daily with as many as 40,000 small comets, vaporizing in the upper atmosphere to
(B) of Earth's being daily bombarded with as many as 40,000 small comets, vaporizing in the upper atmosphere and that
(C) that as much or more than 40,000 small comets daily bombard Earth, vaporizing in the upper atmosphere, and
(D) that daily Earth is bombarded with as much or more than 40,000 small comets that vaporize in the upper atmosphere and that
(E) that Earth is bombarded daily with as many as 40,000 small comets that vaporize in the upper atmosphere and


Option D vs E . " as much or more than 40000" comets " vs " as many as 40000 small comets"
Note that Many is used for countable nouns , relate with the proverb " Too many cooks spoil the dish" .
We all know that this proverb is both grammatically and generally true , since cooks are countable so by reverse engineering many should be used for countable nouns.
Here in the given question comets are countable so we should use "as many as "
E wins