Sentence Correction (SC) | According to surveys by the National Institute on Drug Abuse, about 20

ReedArnoldMPREP - how would you pick (e) over (c) ?

too me (c) seems okay.

here is my analysis on (c)

people keep saying (c) has a comparison problem - i am not sure i see it
- i dont believe" twice ordouble " are comparison markers to begin with

there is a clear antecedent for "those"
-- the antecedent of"those " is 20 % of adults (20 % of adults is plural per my understanding)
-- analogy : 10 % of girls in class 1A are tallerthan those in
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