Hi
EMPOWERgmatVerbal,
Thank you for this broad explanation of this question. Can I add choice F as possible correct choice?
Thanks__
Quote:
Recently physicians have determined that stomach ulcers are not caused by stress, alcohol, or rich foods, but a bacterium that dwells in the mucous lining of the stomach.
A. not caused by stress, alcohol, or rich foods, but
B. not caused by stress, alcohol, or rich foods, but are by
C. caused not by stress, alcohol, or rich foods, but by
D. caused not by stress, alcohol, and rich foods, but
E. caused not by stress, alcohol, and rich foods, but are by
Possible Choice F:F) Recently physicians have determined that stomach ulcers are caused not by stress, alcohol,
and rich foods, but by a bacterium that dwells in the mucous lining of the stomach.
EMPOWERgmatVerbal
Hello Everyone!
This is a great example of a sentence that focuses on parallelism, so let's dive in! To start, let's take a quick look at the original question, and highlight the main differences in orange:
Recently physicians have determined that stomach ulcers are not caused by stress, alcohol, or rich foods, but a bacterium that dwells in the mucous lining of the stomach.
A. not caused by stress, alcohol, or rich foods, but
B. not caused by stress, alcohol, or rich foods, but are by
C. caused not by stress, alcohol, or rich foods, but by
D. caused not by stress, alcohol, and rich foods, but
E. caused not by stress, alcohol, and rich foods, but are by
After a quick glance over the options, there are a few things we can focus on:
1. not caused / caused not (parallelism/idioms)
2. or / and (meaning/lists)
3. but / but are by / but by (parallelism/idioms)
Since we know this question mainly focuses on parallelism, let's tackle #1 & #3 on our list at the same time. This is the idiom structure we're working with here:
not X, but Y
Both X and Y must be written using parallel structure, including word placement, verb tenses, singular/plural, etc. Since the phrase "caused by" is included in this sentence, we need to be careful to make sure it's included in both X and Y only if it appears after the word "not:"
not caused by X, but caused by Y = PARALLEL
not caused by X, but Y = NOT PARALLEL
caused not by X, but by Y = PARALLEL
caused not by X, but caused by Y = NOT PARALLEL
caused not by X, but Y = NOT PARALLEL
Let's add in the end of the sentence to see which options use parallel structure, and eliminate those that don't:
A. not caused by stress, alcohol, or rich foods, but a bacterium that dwells in the mucous lining of the stomach. --> not caused by X, but Y = NOT PARALLEL
B. not caused by stress, alcohol, or rich foods, but are by a bacterium that dwells in the mucous lining of the stomach. --> not caused by X, but are by Y = NOT PARALLEL
C. caused not by stress, alcohol, or rich foods, but by a bacterium that dwells in the mucous lining of the stomach. --> caused not by X, but by Y = PARALLEL
D. caused not by stress, alcohol, and rich foods, but a bacterium that dwells in the mucous lining of the stomach. --> caused not by X, but Y = NOT PARALLEL
E. caused not by stress, alcohol, and rich foods, but are by a bacterium that dwells in the mucous lining of the stomach. --> caused not by X, but are by Y = NOT PARALLEL
There you have it! Option C is correct because it's the only one that uses parallel structure within the idiom "not X, but Y." By focusing on parallelism, you should be able to answer this question pretty quickly!
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