Whereas both Europe and China use standard railroad gauge (1435 mm)

Question

Whereas both Europe and China use standard railroad gauge (1435 mm), Russia deliberately chose the wider “Russian gauge” (1520 mm) that gives greater side-to-side stability in railways cars and, more importantly,  acts as a national defense, so that it would block  foreign army’s supply line and preventing these bordering powers from invading by train.

A. acts as a national defense, so that it would block
B. acts like a national defense, so as to block
C. acts as a national defense, blocking
D. acting as a national defense, blocking
E. acting like a national defense, would bloc

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QMG · Answer

IMO C:

"and" signals parallelism. "gives" needs to be parallel to another verb. Therefore, D & E can be eliminated.

A, B and C left. The correct idiom we need is "act as" and not "act like". So B is out.

Leaves A and C. The ing-Modifier "blocking" in C describes how the "Russian gauge" acts and therefore it is the correct answer ("so that it would  " in choice A is much more wordy than the concise version in C)

NarayanaGupta007 · Answer

hypothetical comparison use LIKE and gerun is nt preferred becoz it will refere to std railroad so flat B

DarkKnight800 · Answer

IMHO the answer should be C. The sentence is trying to say that Russia chose wider “Russian gauge” (1520 mm) and this selection does 2 thing - First gives greater and second acts as National Defence

gives and acts are parallel

The second part of statement expand on how it acts as National Defence and we have modifier expanding on it. But note we already have second half of that modifier written in non underlined portion -->  and preventing these bordering powers from invading by train.

blocking will be a good option to go since it will be parallel to preventing

Hope that helps

100mitra · Answer

All drill downs to A, and C
 Option A: 
Whereas both Europe and China use standard railroad gauge (1435 mm), 
Russia deliberately chose the wider “Russian gauge” (1520 mm) 
that  gives  greater side-to-side stability in railways cars  and,  more importantly, 
  acts  as a national defense,  so that 
it would block   foreign army’s supply line and 
preventing these bordering powers from invading by train.
  Error:   
1. Parallelism error,  so that it would block  not parallel to  preventing  
2. wordy

Option C  
Whereas both Europe and China use standard railroad gauge (1435 mm), 
Russia deliberately chose the wider “Russian gauge” (1520 mm) 
that  gives  greater side-to-side stability in railways cars  and,  more importantly, 
  acts  as a national defense, 
 blocking   foreign army’s supply line and 
 preventing  these bordering powers from invading by train
  Correct: No Parallelism error & clear with intened meaning

Whereas both Europe and China use standard railroad gauge (1435 mm)

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GMAT Sentence Correction (SC - EA only) Questions

Whereas both Europe and China use standard railroad gauge (1435 mm)

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