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 take 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

The answer is 'C' as it will read (Leaching "C" was a well-established method of mineral extraction.) Just remove the , as a method of the extraction of minerals, portion and read the sentence to see if it makes sense and you will choose the right answer.

willkillgmat wrote: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 take 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

The answer is 'C' as it will read (Leaching "C" was a well-established method of mineral extraction.) Just remove the , as a method of the extraction of minerals, portion and read the sentence to see if it makes sense and you will choose the right answer.

Hi All,

I agree that "was a well-established method of mineral extraction" sounds good with leaching... but does "as early as eighteenth century " goes good after "mineral extraction"...

Please share your thoughts...

IMO,

After the modifier we need a verb. So, we can shortlist C & D.

D:was a well-established method of extracting mineral that was as early as the eighteenth century (mineral that was as early as the eighteenth century?)

Leaves us with (C)

rrkan wrote: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 take 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

OA is c

I chose E because I thought It indicates proper tense , but answer is something else. Please share your thoughts

aj5105 wrote:IMO,

After the modifier we need a verb. So, we can shortlist C & D.

D:was a well-established method of extracting mineral that was as early as the eighteenth century (mineral that was as early as the eighteenth century?)

Leaves us with (C)

rrkan wrote: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 take 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

OA is c

I chose E because I thought It indicates proper tense , but answer is something else. Please share your thoughts

Hi Aj,

Had been is also a verb....
can't we use E

In most of the cases, I have seen had (past perfect tense) is used for an event that precedes another event in the past.

IMO, we do not need past perfect tense here.

nervesofsteel wrote:

aj5105 wrote:IMO,

After the modifier we need a verb. So, we can shortlist C & D.

D:was a well-established method of extracting mineral that was as early as the eighteenth century (mineral that was as early as the eighteenth century?)

Leaves us with (C)

rrkan wrote: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 take 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

OA is c

I chose E because I thought It indicates proper tense , but answer is something else. Please share your thoughts

Hi Aj,

Had been is also a verb....
can't we use E