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Expert replies
by satish_iitg » Thu Aug 08, 2013 1:14 am
The new house's front door is secured by an electronic lock; a feature that not only allows residents to lock and unlock the door without physical keys, but also may prevent them from entering the house during a power outage.

a feature that not only allows residents who lock and unlock the door without physical keys, but also may prevent
a feature allowing residents without a physical key to lock or unlock the door, but also possibly preventing
a feature allows residents locking or unlocking the door without physical keys, but also possibly preventing
this feature allows residents to lock and unlock the door without a physical key, but may also prevent
this feature not only allows residents without physical keys to lock or unlock the door, but also prevents

OA is D
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Source: — Sentence Correction |

by sameerballani » Thu Aug 08, 2013 6:21 am
What is the source of this question?
satish_iitg wrote:The new house's front door is secured by an electronic lock; a feature that not only allows residents to lock and unlock the door without physical keys, but also may prevent them from entering the house during a power outage.

a feature that not only allows residents who lock and unlock the door without physical keys, but also may prevent
a feature allowing residents without a physical key to lock or unlock the door, but also possibly preventing
a feature allows residents locking or unlocking the door without physical keys, but also possibly preventing
this feature allows residents to lock and unlock the door without a physical key, but may also prevent
this feature not only allows residents without physical keys to lock or unlock the door, but also prevents

OA is D
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by satish_iitg » Thu Aug 08, 2013 12:51 pm
MGMAT Tests.
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by [email protected] » Thu Aug 08, 2013 5:04 pm
Hi satish_iitg,

This SC has some very specific "style" elements that distinguish the correct answer from the incorrect ones.

Here's what I see when I look at this SC:

1) The prompt references a "front door" - one door - so the style is that there would be "one key" (as opposed to multiple "keys")
2) The end of the sentence discusses a *hypothetical* - that the electronic lock may prevent the residents from entering during a power outage. Hypotheticals tend to use the "infinitive" version of the verb (to *verb*, NOT *verb*ing).

With these two rules, I'd have to pick D.

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Rich
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by s.shivani » Thu Sep 05, 2013 7:05 pm
Hi Rich..
What am not understanding is how the option A is making the sentence a fragment

The new house's front door is secured by an electronic lock;a feature that not only allows residents who lock and unlock the door without physical keys, but also may proven

In the non underlined portion
Sub = The new house's front door
Verb = is


In the underlined portion
Sub = A feature

Verb = preceded by Not only but also = allows & prevents

Pl help by providing solution
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by vinay1983 » Thu Sep 05, 2013 7:38 pm
s.shivani wrote:Hi Rich..
What am not understanding is how the option A is making the sentence a fragment

The new house's front door is secured by an electronic lock;a feature that not only allows residents who lock and unlock the door without physical keys, but also may proven

In the non underlined portion
Sub = The new house's front door
Verb = is


In the underlined portion
Sub = A feature

Verb = preceded by Not only but also = allows & prevents

Pl help by providing solution
As I see it "not only allows but also prevents" is proper usage.

Also I feel "a feature" will have been correct, but none of the options here have "a feature and not only allows but also prevents"

Between those two, I will go for an answer that has "not only allows but also prevents", since it makes more sense (being parallel that is)

Also "that" usage could have been used, but we have to choose the best answer among the choices not the eternal correct one on the GMAT!

Also it is "this feature", which is important here and not the front door.

All said and done, I have a query"Can'y a house door have 2 keys and not "one single key"?
You can, for example never foretell what any one man will do, but you can say with precision what an average number will be up to!
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