leaching

[VIVEK KOUL]

leaching, the recovery of copper from the drainage water of mines, as a method of the extraction of minerals, it was well established as early as the eighteenth century, but until about 25 years ago miners did not realize that bacteria taken an active part in the process.
(A) as a method of the extraction of minerals, it was well established
(B) as a method of the extraction of minerals well established
(C) was a well-established method of mineral extraction
(D) was a well-established method of extracting mineral that was
(E) had been a method of mineral extraction, well established

Code: Select All Code

C

[StaceyKoprince]

Please read (and follow!) the forum guidelines before posting.

We cannot answer a question unless and until a source is posted (and please don't post problems that are on the banned sources list). If you would still like us to address this, please post the author of the question.

[mithra]

I just came across this problem in GMAT Prep 2.

[niksdoon]

Hello Experts, please advice why E cannot be the answer here...I'm not able to understand why do we not need Past perfect here...please help !!

Thanks,
Niks

[ps63739]

C is a shorter sentence and provides the same meaning as E does.

Imagine how would you say -

I had been working there from 1990 to 2000

Or

I worked there from 1990 to 2000.

And also manhattangmat SC book says, use the past perfect if necessary. Here I think 'was' makes good sentence, so 'had been' can be eliminated.

[niksdoon]

Thanks ps63739 for your inputs !!

I agree that we should use past perfect only if necessary. But when I saw usage of two time periods "but until about 25 years ago miners did not realize", I thought of using past perfect.

Can you pls correct my mistake here ?

Niks

[rx_11]

Hi, instructors,

The OA of this question is C. But I don't quite understand the comparison in C. Could u explain what is used to compare with "the eighteenth century"? I can't see which two parts are being compared..

"leaching was a well-established method of mineral extraction as early as the eighteenth century"

Moreover, could u elaborate on why E is wrong?

[jnelson0612]

We seem to be missing a lot of words from the answer choices. If someone could fill these in we could answer the question.