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Morgan Neville, the filmmaker of both Won’t You Be My Neighbor, a historic work on the life of Mr. Rogers, and also of 20 Feet from Stardom, a look into the experience of background singers, is a knowledgeable authority on directing and producing documentaries

If i break the sentence in simple way then, it would be as per below sentence,

Morgan Nevile (MN) is a is a knowledgeable authority on directing and producing documentaries. MN, filmmaker of both X, (appositive/modifier of film X = a historic work on the life of Mr. Rogers), and also Y (appositive/modifier of film X = a look into the experience of background singers).

Here, parallelism is not maintained on both side of parallel connector, both X and Y, instead also is used, which is not preferred by GMAC. In addition, authority means knowledgeable. So, it's usage is redundant.

A. also of 20 Feet from Stardom, a look into the experience of background singers, is a knowledgeable authority on - Incorrect due to above reasons.

B. also 20 Feet from Stardom, a look into the experience of background singers, is a knowledgeable authority about - Incorrect due to same reasons of A. Additionally, incorrect idiom is used here, i.e. authority about.

C. of 20 Feet from Stardom, a look into the experience of background singers, is an authority on - Violates the parallelism, both X and Y.

D. of 20 Feet from Stardom, a look into the experience of background singers, is a knowledgeable authority on - Violates the parallelism, both X and Y.

E. 20 Feet from Stardom, a look into the experience of background singers, is an authority on - Aha perfect sentence with no error.

Morgan Neville, [the filmmaker of both Won’t You Be My Neighbor, (a historic work on the life of Mr. Rogers,) and 20 Feet from Stardom, (a look into the experience of background singers),] is an authority on directing and producing documentaries.

Imo. E
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Answer choice E is correct Both X and Y is correct idiom
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Answer is E

A. also of 20 Feet from Stardom, a look into the experience of background singers, is a knowledgeable authority on - breaks the parallelism

B. also 20 Feet from Stardom, a look into the experience of background singers, is a knowledgeable authority about - redundant use of Also.

C. of 20 Feet from Stardom, a look into the experience of background singers, is an authority on - breaks parallelism

D. of 20 Feet from Stardom, a look into the experience of background singers, is a knowledgeable authority on - Breaks Parallelism

E. 20 Feet from Stardom, a look into the experience of background singers, is an authority on - changes meaning. But, best option among other options if we consider parallelism.
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Official Explanation

Morgan Neville, the filmmaker of both Won’t You Be My Neighbor, a historic work on the life of Mr. Rogers, and also of 20 Feet from Stardom, a look into the experience of background singers, is a knowledgeable authority on directing and producing documentaries

A. also of 20 Feet from Stardom, a look into the experience of background singers, is a knowledgeable authority on

B. also 20 Feet from Stardom, a look into the experience of background singers, is a knowledgeable authority about

C. of 20 Feet from Stardom, a look into the experience of background singers, is an authority on

D. of 20 Feet from Stardom, a look into the experience of background singers, is a knowledgeable authority on

E. 20 Feet from Stardom, a look into the experience of background singers, is an authority on


There are two major differences in this sentence: the beginning and the ending. The beginning deals with the idiom “both A and B.” The issue at the end of the sentence is that it’s redundant to say “knowledgeable authority” when just the word “authority” will do the same job. At the end, we also need to make sure it follows the idiom “X is an authority on Y.” Let’s see how each option handles these issues:

A. also of 20 Feet from Stardom, a look into the experience of background singers, is a knowledgeable authority on
This is INCORRECT. It does not follow the correct structure of the idiom. It says “both X and also of Y” rather than simply leaving the sentence with the correct conjunction “and.” It is also redundant to say “knowledgeable authority.” The only thing this got right is the idiom “X is an authority on Y.”

B. also 20 Feet from Stardom, a look into the experience of background singers, is a knowledgeable authority about
This is INCORRECT. It does not follow the correct structure of the idiom. It says “both X and also Y” rather than simply leaving the sentence with the correct conjunction “and.” It is also redundant to say “knowledgeable authority.” It’s also not idiomatically correct to say “X is an authority about Y.”

C. of 20 Feet from Stardom, a look into the experience of background singers, is an authority on
This is INCORRECT. It does use the more concise “an authority” instead of the redundant “knowledgeable authority.” It also uses the correct “X is an authority on Y” idiom. However, it does not follow the correct structure of the idiom. It says “both X and of Y” rather than simply leaving the sentence with the correct conjunction “and.”

D. of 20 Feet from Stardom, a look into the experience of background singers, is a knowledgeable authority on
This is INCORRECT. It does not follow the correct structure of the idiom. It says “both X and of Y” rather than simply leaving the sentence with the correct conjunction “and.” It is also redundant to say “knowledgeable authority.” The only thing this option gets right is the idiom “X is an authority on Y.”

E. 20 Feet from Stardom, a look into the experience of background singers, is an authority on
This is CORRECT. It follows the correct structure of the idiom by leaving the conjunction “and.” The ending does not have redundancies and uses the correct idiomatic phrasing “X is an authority on Y.”

There you have it - option E is our choice!

Don’t study for the GMAT. Train for it.
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Praveenksinha
Morgan Neville, the filmmaker of both Won’t You Be My Neighbor, a historic work on the life of Mr. Rogers, and also of 20 Feet from Stardom, a look into the experience of background singers, is a knowledgeable authority on directing and producing documentaries

A. also of 20 Feet from Stardom, a look into the experience of background singers, is a knowledgeable authority on:-Incorrect, and also is redundant

B. also 20 Feet from Stardom, a look into the experience of background singers, is a knowledgeable authority about:- Incorrect, and also is redundant

C. of 20 Feet from Stardom, a look into the experience of background singers, is an authority on :- Both X and Y, X and Y must be parallel, here X-"won't you be my Neighbor" and Y -" of 20 feet from stardom" are Not parallel (of makes it nonparallel)

D. of 20 Feet from Stardom, a look into the experience of background singers, is a knowledgeable authority on:- Both X and Y, X and Y must be parallel, here X- "won't you be my Neighbor" and Y -" of 20 feet from stardom" are Not parallel (of makes it nonparallel)

E. 20 Feet from Stardom, a look into the experience of background singers, is an authority on:- Correct

Well done, Praveenksinha! You cracked the code on this one, and provided great explanations for each option. Kudos to you, and we look forward to seeing you back here next week for Pack 13!
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Kartikay22
Morgan Neville, the filmmaker of both Won’t You Be My Neighbor, a historic work on the life of Mr. Rogers, and also of 20 Feet from Stardom, a look into the experience of background singers, is a knowledgeable authority on directing and producing documentaries

A. also of 20 Feet from Stardom, a look into the experience of background singers, is a knowledgeable authority on
( Both - also : Redundancy error
Knowledgeable - authority : Redundant and Wordy
Use of "of" before 20 - Parallelism error) Hence, Incorrect.


B. also 20 Feet from Stardom, a look into the experience of background singers, is a knowledgeable authority about
( Both - also : Redundancy error
Knowledgeable - authority : Redundant and Wordy
About- Wrong preposition) Hence, Incorrect.


C. of 20 Feet from Stardom, a look into the experience of background singers, is an authority on
( Use of "of" before 20 - Parallelism error) Hence, Incorrect.

D. of 20 Feet from Stardom, a look into the experience of background singers, is a knowledgeable authority on
( Use of "of" before 20 - Parallelism error
Knowledgeable - authority : Redundant and Wordy ) Hence, Incorrect.

E. 20 Feet from Stardom, a look into the experience of background singers, is an authority on - Correct

Well done, Kartikay22! You cracked the code on this one, and we look forward to seeing you back here next week for Pack 13! Kudos to you!
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Raxit85
Morgan Neville, the filmmaker of both Won’t You Be My Neighbor, a historic work on the life of Mr. Rogers, and also of 20 Feet from Stardom, a look into the experience of background singers, is a knowledgeable authority on directing and producing documentaries

If i break the sentence in simple way then, it would be as per below sentence,

Morgan Nevile (MN) is a is a knowledgeable authority on directing and producing documentaries. MN, filmmaker of both X, (appositive/modifier of film X = a historic work on the life of Mr. Rogers), and also Y (appositive/modifier of film X = a look into the experience of background singers).

Here, parallelism is not maintained on both side of parallel connector, both X and Y, instead also is used, which is not preferred by GMAC. In addition, authority means knowledgeable. So, it's usage is redundant.

A. also of 20 Feet from Stardom, a look into the experience of background singers, is a knowledgeable authority on - Incorrect due to above reasons.

B. also 20 Feet from Stardom, a look into the experience of background singers, is a knowledgeable authority about - Incorrect due to same reasons of A. Additionally, incorrect idiom is used here, i.e. authority about.

C. of 20 Feet from Stardom, a look into the experience of background singers, is an authority on - Violates the parallelism, both X and Y.

D. of 20 Feet from Stardom, a look into the experience of background singers, is a knowledgeable authority on - Violates the parallelism, both X and Y.

E. 20 Feet from Stardom, a look into the experience of background singers, is an authority on - Aha perfect sentence with no error.

Morgan Neville, [the filmmaker of both Won’t You Be My Neighbor, (a historic work on the life of Mr. Rogers,) and 20 Feet from Stardom, (a look into the experience of background singers),] is an authority on directing and producing documentaries.

Imo. E

Well done, Raxit85! You cracked the code on this one! Great explanations as always, too! Kudos to you!
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saro
Answer choice E is correct Both X and Y is correct idiom

You cracked the code, saro!

For your answers to qualify for the contest, please make sure to break down what is right/wrong with each option. That helps other students see your thought process and better study on their own. :)
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Answer is E

A. also of 20 Feet from Stardom, a look into the experience of background singers, is a knowledgeable authority on - breaks the parallelism

B. also 20 Feet from Stardom, a look into the experience of background singers, is a knowledgeable authority about - redundant use of Also.

C. of 20 Feet from Stardom, a look into the experience of background singers, is an authority on - breaks parallelism

D. of 20 Feet from Stardom, a look into the experience of background singers, is a knowledgeable authority on - Breaks Parallelism

E. 20 Feet from Stardom, a look into the experience of background singers, is an authority on - changes meaning. But, best option among other options if we consider parallelism.

Well done, aniket2045! You cracked the code on this one, and we appreciate the clear and concise explanations for each option! We can't wait to see you back next week for Pack 13! Kudos to you!
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This is a rather straight forward question.

The correct idiom is "of both X and Y", so A / B / C / D are immediately eliminated, leaving E as the correct answer.

Note:
- "Both X and also Y" is almost always incorrect in GMAT

- Both "of both X and Y" and "both of X and of Y" are acceptable. You should not repeat what precedes "both, and should repeat what follows.

Eg. I want to both eat and sleep.
Eg. I want both to eat and to sleep.


Morgan Neville, the filmmaker of both Won’t You Be My Neighbor, a historic work on the life of Mr. Rogers, and also of 20 Feet from Stardom, a look into the experience of background singers, is a knowledgeable authority on directing and producing documentaries

A. also of 20 Feet from Stardom, a look into the experience of background singers, is a knowledgeable authority on

B. also 20 Feet from Stardom, a look into the experience of background singers, is a knowledgeable authority about

C. of 20 Feet from Stardom, a look into the experience of background singers, is an authority on

D. of 20 Feet from Stardom, a look into the experience of background singers, is a knowledgeable authority on

E. 20 Feet from Stardom, a look into the experience of background singers, is an authority on

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