A federal government survey taken in 1997 showed that during the 12 mo

Its a question based on ||ism. As the first element is in double past, rest 2 should also be in double past.
Hence B.

A federal government survey taken in 1997 showed that during the 12 months preceding the survey,36 percent of the U.S. population had tried marijuana, cocaine, or other illicit drugs,71 percent of the population were smoking cigarettes, and 82 percent tried alcoholic beverages.

A) were smoking cigarettes, and 82 percent
B) had smoked cigarettes, and 82 percent had --> correct
C) smoked cigarettes, and that 82 percent
D) smoked cigarettes, and 82 percent had
E) will be smoking cigarettes, and 82 percent

OA: B

Official Answer
“Had smoked cigarettes, and 82 percent had” is correct for two reasons.
First of all, it’s the past perfect tense, which should always be used to describe actions occurring before other actions in the past. Here, before the survey was taken in 1997, people had used drugs, cigarettes, and alcohol.
Second, “had smoked cigarettes, and 82 percent had” is parallel to the elements of the sentence that are not underlined and that therefore cannot be changed.
Eliminate (A), (C), (D), and (E) because they use tenses that don’t make sense given the sequence of events in the sentence and because they do not put similar elements in a similar form.
Only choice (B) corrects both problems.

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