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

[quote="Nick90"] Cities (plural) so was is wrong and. Were is correct
A : was
B : was
C : no error ( correct , which refers to cities also were used correctly relates with cities)
D: being
E: characterised can refer to destruction (meaning ambiguity)

IMO C

You are correct which is a relative clause and it must be as Non essential cases and a comma beforeit.

Modifier rule for VERB-ED : Verb-ed modify the closet noun

For ex : The spaceship, designed to withstand to check the radiation of the
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