V01-41

Question

The adoption of either method of extraction,  open-pit mining or solution mining , will require miners to be certified in the use of safety equipment.

A. open-pit mining or solution mining
B. open-pit mining and solution mining
C. open-pit and solution minings
D. open-pit mining, including solution mining
E. mining by open-pit or by solution

Bunuel · Answer

Official Solution:

The adoption of either method of extraction,  open-pit mining or solution mining , will require miners to be certified in the use of safety equipment.

A. open-pit mining or solution mining
B. open-pit mining and solution mining
C. open-pit and solution minings
D. open-pit mining, including solution mining
E. mining by open-pit or by solution

This sentence requires the grammatically correct extension of the phrase  either method of extraction . The underlined portion must show contrast and agree with the singular word  either  by using the conjunction  or .
 
 A. CORRECT.  This option correctly extends the phrase in the first part of the sentence to read  either…open-pit mining or solution mining.  
 
B.  And  is an incorrect conjunction, because it does not agree with  either .
 
C. This option may seem more concise, but  and  is incorrect because it does not agree with  either , and  minings  should not be plural.
 
D. In this option, the meaning of the sentence has been changed to incorrectly suggest that  solution mining  is a kind of  open-pit mining .
 
E.  Mining  is redundant in this context, because it repeats the words  method of extraction . This word order also makes the sentence awkward and confusing.

Answer: A

lorenzo393 · Answer

I have a doubt: the idiom is either X or Y but could also be either X,Y or Z?

sayantanc2k · Answer

There may be difference opinion among grammarians whether "either..or" structure can be used for more than two options. However in GMAT such dubious points are not generally tested. (Neither it is tested in this question.)

rrkiitm · Answer

It looks like "Open Pit mining or Solution mining" is used as an non essential modifier here. With or without the underlined portion the sentence still makes sense? If true, Open Pit mining AND Solution mining makes sense here. Isnt it?

AdityaHongunti · Answer

this does not make sense
you expect to follow the either..or.. pattern and insert the menthod of extraction in two commas

either method of extraction? means there are two methods of extractions X and Y
either method of extraction wil.....
you cannot use OR here , because if you do then soluthion mining cannot be considered as a METHOD OF EXTR because the method of extr now plays as a modifier of noun pit mining.

we need "and" as we are choosing either from X and Y. 
to use "or" you have to drop "method of extr from the sentence.
I would like to know which source was this replicated or where did u get this usage from. I'd like to correct my understanding if I'm wrong

gvij2017 · Answer

I have same issue with this SC problem. 
And I do agree with your explanation.

vps01011989 · Answer

The clause between commas is used as a modifier for two methods of extraction. Using conjunction 'or' does not modify two methods. Conjunction 'and' should be used.

Jerrymaguire · Answer

Any updates to this question? Why can't "And" work?

martinfzb · Answer

The adoption of either x or y is an familiar idiom, but the difficult point is on the 
understanding of extraction, open-pit mining.
Extraction, open-pit mining is a type of mining and solution is another type of mining.

rsvelc · Answer

Hi, I shortlisted A and E, I eliminated E for the usage of "by" which didn't seem concise. Can this be a valid explanation or just "because it didn't sound right"?

V01-41

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