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9. Concerned that economic recovery is not as complete as previously hoped, wealthier consumers have begun to limit travel, slowing investments, to decrease overall spending on nonessential items, creating further financial setbacks.
OBVIOUSLY this is a parallelism issue, joined with a modifier issue (participles: -ing words, which modify the entire preceding clause, typically showing its result). We just need to find the answer that gets both of these right.
(A) have begun to limit travel, slowing investments, to decrease overall spending on nonessential items
PROBLEM: We can't say "to limit", "slowing", and then "to decrease". Those aren't parallel.
(B) have begun to limit travel, slow investments, decrease overall nonessential spending
PROBLEM: While "limit", "slow", and "decrease" are all parallel (the first "to" distributes, so you don't need to repeat it for each one), the list would then have to end (because the next thing after a comma is a participle). But that doesn't happen here, because we would need to see the word "and" before the word "decrease", signaling the end of the list.
(C) have begun limiting travel, slow investing, and decrease overall spending on nonessential items
PROBLEM: Now the list starts AFTER the word "limiting", as if we're limiting "travel" and "slow investing", which makes no sense.
(D) have begun to limit travel and slow investments, decreasing nonessential spending overall and
ANSWER: Now our first list has only two items in it "limit" and "slow". These two verbs are parallel. Then we get a parallel set of participles "decreasing" and "creating", which are also parallel. Notice also how the participles "decreasing" and "creating" do EXACTLY what I said they would, namely describe the RESULT of the previous clause (the limiting of travel and the slowing of investments).
(E) have begun to limit travel, slow investments, and decrease overall spending on nonessential items for
PROBLEM: The first few items are parallel: "limit" "slow" and "decrease". But now we have a prepositional modifier "for creating further financial setbacks", which appears to be modifying "items". This doesn't make any sense. Notice how the participial modifiers in answer choice D does exactly what I said it would, they describe the RESULTS of limiting travel and slowing investments (the preceding clause).
Hope that makes sense!
Tommy Wallach | Manhattan GMAT Instructor | San Francisco
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