General contracting firms are investigating changes in construction techniques that would permit contractors to reduce the time required to complete construction of a building, decrease the amount of raw material needed during construction, and to avoid changes that require contractors that revise blueprints and redraft working plans.


A. decrease the amount of raw material needed during construction, and to avoid changes that require contractors that revise blueprints

B. decrease the amount of raw material needed during construction, and avoiding changes that require contractors revising blueprints

C. to decrease the amount of raw material needed during construction, and avoiding changes that require contractors to revise blueprints

D. to decrease the amount of raw material needed during construction, avoiding changes that require contractors that revise blueprints

E. to decrease the amount of raw material needed during construction, and to avoid changes that require contractors to revise blueprints
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Simple strategy:
“Once you’ve eliminated the impossible, whatever remains, however improbable, must be the truth.”

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My Notes:
Reading comprehension | Critical Reasoning | Absolute Phrases | Subjunctive Mood

Question Explanation

The underlined portion of the sentence contains part of a list, so check that all items in the list are parallel. The list begins with the infinitive to reduce in the non-underlined portion. The list continues with the verb decrease and the infinitive to avoid. The preposition to appears before the first and third verbs in the list, but not the second, so this is a parallel construction error. Eliminate choice A and look for any obvious repeaters. Because there are no obvious repeaters, evaluate the remaining answer choices individually, looking for reasons to eliminate each.

Choice B contains the list to reduce, decrease, and avoiding. Because these verb forms are not parallel, this is a parallel construction error. Eliminate choice B. Choice C contains the list to reduce, to decrease, and avoiding. Because these verb forms are not parallel, this is a parallel construction error. Eliminate choice C. Choice D contains the list to reduce, to decrease, and avoiding. Because these verb forms are not parallel, this is a parallel construction error. Eliminate choice D. Choice E fixes the original parallel construction error by changing the list to the parallel verbs to reduce, to decrease, and to avoid. Choice E introduces no new errors, so keep choice E.

Alternatively, if it is difficult to spot which grammar rule the sentence is testing, another strategy is to try to identify an error from the answers by looking for either a 2/3 split or differences among the answers. Since three answer choices use the infinitive to decrease and the others use only the verb decrease, this difference is an indication to look for parallel construction errors.

Choice A: No. The verb forms to reduce, decrease, and to avoid are not parallel. Parallel construction.

Choice B: No. The verb forms to reduce, decrease, and avoiding are not parallel. Parallel construction.

Choice C: No. The verb forms to reduce, to decrease, and avoiding are not parallel. Parallel construction.

Choice D: No. The verb forms to reduce, to decrease, and avoiding are not parallel. Parallel construction.

Choice E: Correct.

The correct answer is choice E.
_________________

Thanks!
Do give some kudos.

Simple strategy:
“Once you’ve eliminated the impossible, whatever remains, however improbable, must be the truth.”

Want to improve your Score:
GMAT Ninja YouTube! Series 1| GMAT Ninja YouTube! Series 2 | How to Improve GMAT Quant from Q49 to a Perfect Q51

My Notes:
Reading comprehension | Critical Reasoning | Absolute Phrases | Subjunctive Mood