Our Premium and Ultimate plans guarantee up to 90+ points score increase or your money back.
We cover every section of the GMAT with in-depth lessons, 5000+ practice questions and realistic practice tests.
Study whenever and wherever you want with our iOS and Android mobile apps.
Adaptive learning technology focuses on your academic weaknesses.
In assessing the design for a study on the causes of hepatitis B infection in institutional settings, a reviewer pointed out that to qualify as a valid scientific study, the control group would have to include the same proportion of foreign-born employees as the test group.
This answer choice is grammatically incorrect. A comparative section beginning with as should always include a conjugated verb. The comparative section in this answer choice (as the test group), however, does not.[[snippet]]
This answer choice is grammatically incorrect. A comparative section beginning with as should always include a conjugated verb. The comparative section in this answer choice (as the proportion in the test group), however, does not.[[snippet]]
This answer choice is grammatically incorrect and illogical. The comparative construction requires that the things compared be logically parallel.
This answer choice illogically compares the test group itself with the proportion of foreign born employees included in that group. Instead, the control group and the test group should be compared in terms of the proportion of foreign born employees which each group has.
In addition, this answer choice makes incorrect grammatical use of the Future Past Perfect tense (would have included), which should only be used in conditional sentences in which the situations could have happened but did not.
While this answer choice corrects the comparative mistake in the original question, by including a conjugated verb in the comparative section beginning with as, it is stylistically flawed. The passive construction were included in is wordy and redundant. There is another answer choice that is grammatically sound, logical and concise. Look for it![[snippet]]
This sentence makes correct grammatical use of a comparative structure and is stylistically sound as it uses a conjugated verb in the second part of the comparison (as the test group does).[[snippet]]