OFFICIAL EXPLANATION



THE PROMPT

• Issues?

Diction and style.

I post this type of question because I want you to be ready for anything, including:
-- questions that are not amenable to using "splits"
-- questions that take you outside of the "grammar rule" comfort zone (you cannot possibly memorize every grammar rule and at some point must also train your eye to spot problems in diction and style), and
-- questions that require you to compare the choices. I want you to be accustomed to comparing two options and asking, "Which one is better than the other?" (Or, as someone at MGMAT put it: Which is better? Which is worse?)

THE OPTIONS


• users are allowed = weird logic and/or meaning
→ Are allowed? Were people were not allowed to use the technology before now?
→ who or what finally gave users permission to create physical items from digital blueprints?

• are evidence and are allowed: these two are passive forms of the verbs evidence and allow
(Yes, evidence can be a verb that means "prove.")
→ active voice is not always preferred to passive voice, but flag passive voice
KEEP, very tentatively


• evidence of far-fetched Star Trek ideas being a modern reality is a convoluted train wreck.
→ be slightly suspicious of being
→ meaning issue: being, which places us almost entirely in the present, does not mean the same thing that have become means.
Logically, have become is better than being.

Especially when we want to emphasize the result of something that just recently developed, we use present perfect (HAVE + past participle):
→ Compare:
The hospitals in Southern California have reached 100 percent capacity. No ICU beds are available.
The full hospitals in Southern California are evidence of capacity being at 100 percent. No ICU beds are available.
-- the second sentence is passive, wordier than necessary, and flabby.

• still, no hard grammar error exists
Options A and B are both bad but not necessarily ungrammatical.
KEEP, very tentatively

• is supported is the passive form of the verb support, a form that makes this already long sentence even more leaden

• strange meaning: whether fanciful ideas shown on Star Trek have become a reality is not really an idea but a fact.
That is, either the fanciful ideas have become a reality or they have not.
If so, we would talk about the fact that Star Trek ideas have become a reality (not the idea that they have become a reality).
If not, we would talk about the fact that Star Trek ideas have not become a reality (as opposed to the idea that they have not become a reality).

• the sentence has too many unnecessary words
→ for example, we do not need both "the invention of" and the which clause that explains what 3-D prints do.
In fact, we could easily omit the first phrase but not the second.

• at this point I think that options A, B, and C are equally bad.
KEEP, very tentatively

• Boom. This sentence is so much better than the preceding three options
→ it is clear and concise
→ it uses a dynamic noun descriptor ("Proving that XYZ")
→ it uses an active verb: . . . 3-D printers allow . . .

• Do not be thrown by the fact that this option does not contain the word "evidence."
The option does not need to do so.
What is evidence? Proof!

"Proving" conveys the same logic that "evidence" does.

• Option D is better by far than options A, B, and C. Eliminate those three.
KEEP D


• As proof of far-fetched Star Trek ideas being a reality is yet another convoluted phrase.

• Being in this option should be having become (or better yet, have become, but this option would not support that form of the verb)
This issue is the same as the issue in option B.

• Easiest (and fastest) line of analysis: is option E better than option D?
Nope. Not even close.
ELIMINATE E

The best answer is D.

NOTES

Takeaways:
• option A does not determine intended meaning.
The most grammatical, logical, and well-written sentence is the one with the intended meaning.

• On questions that are full of "mushy" (soft) details, stand back. You need a satellite's view.
And you need one other thing: to read in English every day.
SC is the easiest area to improve in, but not if you fail to read.

Human beings learn patterns. We learn patterns even when we are not looking for them.

Take 30 minutes away from TV, TikTok, Instagram, Twitter, FB, YouTube, or whatever your app is.
Read.

COMMENTS

callmeDP , welcome to SC Butler.

Color me impressed!
THe analysis on this thread is incisive—even if on occasion it led to an incorrect answer.

Those of you who reasoned yourself to an incorrect answer nonetheless displayed solid critical thinking skills.

Those of you who reasoned yourself to the correct answer showed stellar analytical skills and the all-important flexible thinking.

Kudos to those with the correct answer. (As far as I can tell from the time-stamps, they came in before OA was revealed. On Saturdays, sometimes I choose 2 days before the OA is revealed.)
All are well explained. Nicely done.

What are the 3-D printers? Evidence or Proof?

Proof - demonstrates something to be real or true.
Evidence- leads one to believe something to be real or true.

In the actual sentence, the printers are not proving any idea or concept or belief, they are just demonstrating that something that was thought once has turned to reality now.


A) Revolutionary 3-D printers are evidence that far-fetched Star Trek ideas have become a reality, as users are allowed to create physical items from digital blueprints.
Looks correct. Hold on.
B) Revolutionary 3-D printers, which allow users to create physical items from digital blueprints, are evidence of far-fetched Star Trek ideas being a modern reality.
If we remove the non-essential modifiers, the sentence fails to convey how the printers are evidence.
C) The idea that far-fetched Star Trek ideas have become a reality is supported by the invention of revolutionary 3-D printers, which allow users to create physical items from digital blueprints.
The idea that XYZ ideas... definitely not a good construction .
D) Proving that far-fetched Star Trek ideas have become a reality, revolutionary 3-D printers allow users to create physical items from digital blueprints.
The printers are not proving any idea or concept or belief, they are just demonstrating that something that was thought once has turned to reality now.
E) As proof of far-fetched Star Trek ideas being a reality, revolu¬tionary 3-D printers allow users to create physical items from digital blueprints.
The printers are not proving any idea or concept or belief, they are just demonstrating that something that was thought once has turned to reality now.

IMO A

Revolutionary 3-D printers are evidence that far-fetched Star Trek ideas have become a reality, as users are allowed to create physical items from digital blueprints.

Main Subject-3-D printers


A) Revolutionary 3-D printers are evidence that far-fetched Star Trek ideas have become a reality, as users are allowed to create physical items from digital blueprints. - Looks okay. All SV match. keep

B) Revolutionary 3-D printers, which allow users to create physical items from digital blueprints, are evidence of far-fetched Star Trek ideas being a modern reality. - Looks fine. Correct placement of modifier, the meaning is more clear than A. keep

C) The idea that far-fetched Star Trek ideas have become a reality is supported by the invention of revolutionary 3-D printers, which allow users to create physical items from digital blueprints. - Incorrect subject

D) Proving that far-fetched Star Trek ideas have become a reality, revolutionary 3-D printers allow users to create physical items from digital blueprints. - incorrect subject

E) As proof of far-fetched Star Trek ideas being a reality, revolu¬tionary 3-D printers allow users to create physical items from digital blueprints. - incorrect subject

IMO B
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IMO B

Revolutionary 3-D printers are evidence that far-fetched Star Trek ideas have become a reality, as users are allowed to create physical items from digital blueprints.

Revolutionary 3-D printers are evidence that <of something> far-fetched Star Trek ideas have become a reality, as users are allowed to create physical items from digital blueprints.

A) Revolutionary 3-D printers are evidence that far-fetched Star Trek ideas have become a reality, as users are allowed to create physical items from digital blueprints.

B) Revolutionary 3-D printers, which allow users to create physical items from digital blueprints, are evidence of far-fetched Star Trek ideas being a modern reality.
Crisp and correct.
X,which allow users to create Y, are evidence of Z being a modern reality.

C) The idea that far-fetched Star Trek ideas have become a reality is supported by the invention of revolutionary 3-D printers, which allow users to create physical items from digital blueprints.
Means that idea is supported - we do not know if that's a reality yet?

D) Proving that far-fetched Star Trek ideas have become a reality, revolutionary 3-D printers allow users to create physical items from digital blueprints.
Tense usage mismatch.

E) As proof of far-fetched Star Trek ideas being a reality, revolu¬tionary 3-D printers allow users to create physical items from digital blueprints.

My answer is (D). It took me 59 seconds.

(A) I took issue with ", as users are allowed to create physical items from digital blueprints"
1. Typically, we use comma when subordinate clause is before the main clause, but we do not use comma when subordinate clause is after the main clause.
2. "As" can introduce a clause for time or for reason. In strictly clear writing, avoid "as" but use "when" or "because" as appropriate.
(B) "being a modern reality" is awkward. Also, if there is a choice, prefer verb (prove) to noun (evidence).
(C) Prefer active voice to passive voice (is supported)
(D) Nothing wrong with this version. No passive voice. "Prove" is used as opposed to noun ("evidence").
(E) "being a reality" is awkward.

Revolutionary 3-D printers are evidence that far-fetched Star Trek ideas have become a reality, as users are allowed to create physical items from digital blueprints.



A) Revolutionary 3-D printers are evidence that far-fetched Star Trek ideas have become a reality, as users are allowed to create physical items from digital blueprints.

B) Revolutionary 3-D printers, which allow users to create physical items from digital blueprints, are evidence of far-fetched Star Trek ideas being a modern reality.

C) The idea that far-fetched Star Trek ideas have become a reality is supported by the invention of revolutionary 3-D printers, which allow users to create physical items from digital blueprints.

D) Proving that far-fetched Star Trek ideas have become a reality, revolutionary 3-D printers allow users to create physical items from digital blueprints.

E) As proof of far-fetched Star Trek ideas being a reality, revolu¬tionary 3-D printers allow users to create physical items from digital blueprints.


answer should be c )

a is wrong because as it does not tie revolutionary printers to being evidence of smth
b is wrong since evidence of is not preferable language and evidence that should be used

d is wrong since it somehow says that printers prove and allow which does not makes sense with subject

e seems wrong reasoning

Revolutionary 3-D printers are evidence that far-fetched Star Trek ideas have become a reality, as users are allowed to create physical items from digital blueprints.

First of all, Thanks for posting this question. It is a fun to solve it.

I read the question twice to understand following 2 points,
1) what is evidence! Is Revolutionary 3-D printers or something 3-D printers made? I take something made is an evidence.
2) If something is done, just completed, we use present perfect tense, rather than being.

A) Revolutionary 3-D printers are evidence that far-fetched Star Trek ideas have become a reality, as users are allowed to create physical items from digital blueprints.-> Why we are saying "Revolutionary 3-D printers are evidence...." No! Actually, "Star Trek ideas have become a reality..." is an evidence.

B) Revolutionary 3-D printers, which allow users to create physical items from digital blueprints, are evidence of far-fetched Star Trek ideas being a modern reality.-> Why we do say, "Star Trek ideas being a modern reality.", "Have become" is better to use.

C) The idea that far-fetched Star Trek ideas have become a reality is supported by the invention of revolutionary 3-D printers, which allow users to create physical items from digital blueprints.-> Oh, No! "The idea is supported by the invention... " It changed the meaning of sentence.

D) Proving that far-fetched Star Trek ideas have become a reality, revolutionary 3-D printers allow users to create physical items from digital blueprints.-> Proving is modifying "revolutionary 3-D printers"...and It makes sense. I didn't get another error. Let's keep it.

E) As proof of far-fetched Star Trek ideas being a reality, revolu¬tionary 3-D printers allow users to create physical items from digital blueprints.-> Why we do say, "Star Trek ideas being a reality....", "Have become" is better to use.

So, I think D.

Revolutionary 3-D printers are evidence that far-fetched Star Trek ideas have become a reality, as users are allowed to create physical items from digital blueprints.



A) Revolutionary 3-D printers are evidence that far-fetched Star Trek ideas have become a reality, as users are allowed to create physical items from digital blueprints. Incorrect

modifier error - as uses wrong

B) Revolutionary 3-D printers, which allow users to create physical items from digital blueprints, are evidence of far-fetched Star Trek ideas being a modern reality. Incorrect

evidence of uses wrong, evidence that correct
meaning change - being uses wrong, changes meaning

C) The idea that far-fetched Star Trek ideas have become a reality is supported by the invention of revolutionary 3-D printers, which allow users to create physical items from digital blueprints. Incorrect

double idea uses wrong

D) Proving that far-fetched Star Trek ideas have become a reality, revolutionary 3-D printers allow users to create physical items from digital blueprints. Correct

E) As proof of far-fetched Star Trek ideas being a reality, revolu¬tionary 3-D printers allow users to create physical items from digital blueprints. Incorrect

modifier error - as uses wrong, being uses wrong

IMO A

Its a Tough one .. IMO D
Here is my Assessment

A) Revolutionary 3-D printers are evidence that far-fetched Star Trek ideas have become a reality, as users are allowed to create physical items from digital blueprints. - A is wrong because Evidence That is wrong use of Preposition

B) Revolutionary 3-D printers, which allow users to create physical items from digital blueprints, are evidence of far-fetched Star Trek ideas being a modern reality. - As far as possible avoid being in GMAT -- In this case being changes meaning of the sentence hence B is out .

C) The idea that far-fetched Star Trek ideas have become a reality is supported by the invention of revolutionary 3-D printers, which allow users to create physical items from digital blueprints. - Redundancy error.

D) Proving that far-fetched Star Trek ideas have become a reality, revolutionary 3-D printers allow users to create physical items from digital blueprints. - Crisp .. Active Voice - this is the answer.

E) As proof of far-fetched Star Trek ideas being a reality, revolu¬tionary 3-D printers allow users to create physical items from digital blueprints.---- Meaning Error.

The official explanation is here.

TarunKumar1234 , you are very welcome.
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