For many revisionist historians, Christopher Columbus has come to personify devastation and enslavement in the name of progress that has decimated native peoples of the Western Hemisphere.
A. devastation and enslavement in the name of progress that has decimated native peoples of the Western Hemisphere
B. devastation and enslavement in the name of progress by which native peoples of the Western Hemisphere decimated
C. devastating and enslaving in the name of progress those native peoples of the Western Hemisphere which in the name of progress are decimated
D. devastating and enslaving those native peoples of the western Hemisphere which in the name of progress are decimated
E. the devastation and enslavement in the name of progress that have decimated the native peoples of the Western Hemisphere

OA : A

I could not understand what "that" is referring to in the correct option A. According to the right answer it says "progress" has decimated native peoples but logically how is that possible. Please guide me if correct.
Also, then I though that the phrase "X in the name of Y" could mean that Y will give opposite result of X and could be true. Am I thinking in the right direction? please help

I marked E as the answer but considering "the" in "the devastation and enslavement", which makes it a compound noun, I found that I mistook the subject verb agreement, and after "that" only singular verb can come in this option.
Could you also explain if I am on the right track for E

The source of this question is a definitely not 1000SC document but a document of GMATprep questions I have.

that' without a comma - they must modify the immediately preceding noun. "progress"

As per you, then it is the "progress" which decimated the native people. This does not make any sense.

Experts please help!

hitesh, you can't use "a random document of GMATPrep problems" as a source. please read the forum rules -- we need ORIGINAL sources.

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