GMAT Sentence Correction (SC) | SC:Conquistadors began the destruction of South American

This is definitely not one of ours. It's from Manhattan Review (an unrelated group), and I don't think it's valid.

The original version actually uses "populations" in both C and E, and the official explanation eliminates C solely on the grounds of concision. This is not likely to happen on the GMAT. In fact, one could easily counter-argue that "which were" adds clarity, making it easier to see immediately that we are characterizing the cities rather than the destruction.

In
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