By 1918, advances in tractor technology had led to increased yield,

Question

By 1918, advances in tractor technology had led to increased yield, efficiency of labor,  profit per square acre, and reduced the amount of time  in which fields were planted.

A:profit per square acre, and reduced the amount of time

B:profit per square acre, and had reduced the amount of time

C:profit per square acre, and a reduction in the amount of time

D:and profit per square acre, but the amount of time was reduced

E:and profit per square acre while reducing the amount of time

KarishmaB · Accepted Answer

Structure of the sentence:
Advances had led to increased A, B and C while reducing D.

A - yield, 
B - efficiency of labor, 
C - profit per square acre

"and" should be before "profit per square acre" because "reducing the amount of time" cannot be a part of the list.

Also, "in which fields were planted" modifies "amount of time".

So (E) is correct.

Shubhasish · Answer

There are two possibilities
1) (increased yield, efficiency of labour, profit per square acre, and reduced the amount of time) represents a list (A,B,C)
2) (increased yield, efficiency of labour, profit per square acre) in a list and the part (reduced the amount of time) show contrast (D,E)

Now read the sentence again, "Advances in tractor technology had led to ...". The sentence is not trying to show contrast. Hence, eliminate D and E

Now possibility 1, the sentence (increased yield, efficiency of labour, profit per square acre, and reduced the amount of time) is a list. If so, then there should be a noun after "and". 
Hence option C stands.

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arun6765 · Answer

+1 for E

list with increased end with  and profit per square acre , while reducing the amount of time

Hope it helps.

Shubhasish · Answer

There is no comma in option E.

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arun6765 · Answer

Shubhasish 
We have a comma before the last item of the list "and profit per square acre".

While can exist without comma in this sentence. This is totally my view experts can enlighten you more regarding this issue.

Hope it helps.

Shubhasish · Answer

I am not concerned about while, but about "reducing". A verb+ing without a comma modifies the preceding noun, profits per square acre. If there had been a comma before while, then reducing would have modified the preceding clause.

I just hope that is the case cause the intended meaning of this SC is X led to increased a,b and c, while reducing d.

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surendrasaini1 · Answer

By 1918, advances in tractor technology had led to increased yield, efficiency of labor,  profit per square acre, and reduced the amount of time  in which fields were planted.

A:profit per square acre, and reduced the amount of time(led to X, Y, and Z construction to be followed, reduced is used as a verb and is parallel to led, which is incorrect )

B:profit per square acre, and had reduced the amount of time(past perfect tense is not required)

C:profit per square acre, and a reduction in the amount of time( though didn't find any error but in comparison with E ,little change in meaning)keep

D:and profit per square acre, but the amount of time was reduced (contrast is not required in meaning)

E:and profit per square acre while reducing the amount of time( seems to to be correct,meaning suggests that advances led to X,Y,and Z at the same time reduced the time of plantation)

Will go with choice E but don't have any strong basis for rejecting choice C.

Thanks

cngthanh190 · Answer

I go with E since it maintains the structure "S + V + O While V-ing".

rahul6019 · Answer

Very good question...Right answer should either be D or E as it says advances in tractor technology had led to increased yield, efficiency of labor, profit per square acre followed by and reduced amount of time, so increased stands for all 3 elements i.e. yield, efficiency of labor and profit per square acre and hence and is required before profit per square acre to complete this list.

We can eliminate A, B and C for this.

Between D and E, E conveys proper meaning of an entity causing an increase in X while reducing Y. So E is correct.

We can eliminate A, B and C for this.

Between D and E, E conveys proper meaning of an entity causing an increase in X while reducing Y. So E is correct.

aragonn · Answer

Question Explanation: 
Since the underlined portion of the sentence contains the conjunction and, check whether the items before and after the conjunction are joined correctly. In this case, profit per square acre and reduced the amount of time are joined with and, but profit per square acre should actually be joined using and to yield and efficiency of labor from earlier in the sentence (since all are increased) while the amount of time should be treated separately since it is reduced. This is a clauses and connectors error, so eliminate choice A and look for any obvious repeaters. Choices B and C are obvious repeaters since they also begin with profit per square acre (without and), so eliminate choices B and C. Now evaluate the remaining answer choices individually, looking for reasons to eliminate each.

Choice D correctly connects profit per square acre with yield and efficiency of labor using and but introduces a parallel construction error since amount of time was reduced is not parallel to increased, so eliminate choice D. Choice E correctly connects profit per square acre with yield and efficiency of labor using and and introduces no new errors, so keep choice E.

Alternatively, if it is difficult to spot the grammar rule the sentence is testing, another strategy is to identify an error from the answers by looking for either a 2/3 split or differences among the answer choices. Because three of the answer choices begin with profit per square acre and two of them begin with and profit per square acre, this difference is an indication to look for clauses and connector errors.

Choice A: No. Profit per square acre is not correctly joined to the sentence using and. Clauses & Connectors.

Choice B: No. Profit per square acre is not correctly joined to the sentence using and. Clauses & Connectors.

Choice C: No. Profit per square acre is not correctly joined to the sentence using and. Clauses & Connectors.

Choice D: No. Amount of time was reduced is not parallel to increased. Parallel Construction.

Choice E: Correct.

The correct answer is choice E.

AdityaHongunti · Answer

By 1918, advances in tractor technology had led to increased yield, efficiency of labor, profit per square acre, and reduced the amount of time in which fields were planted.

meaning : Advances increased : 1. yeild 2. efficiency 3. profit per square
 Advances reduced : amount of time

error : "and" before "profit" . why?? the original statement wrongly implies : advances increased.... reduced . How can we increase and reduce the same time?
 
eliminate A B C

D:and profit per square acre, but the amount of time was reduced 
- INCORRECT - remedies the parallelism error . But introduces another error : "but" . We do not need a contrast. The advances have only been mentioned for their positive effect. reduction in time is not a negative outcome of advances. SO "but" is wrong.

E:and profit per square acre while reducing the amount of time
- CORRECT - "while" means "at the same time/period" .. so advances have done X,Y, and Z WHILE reducing bla bla bla.
Here "reducing " is correct as we are just stating more info about results of advances. 
"while they have reduced" would have been right but would be too wordy for GMAT.

further doubts? ping me

Mpuneet · Answer

The word ‘and’ is not the right way to connect ‘profit per square acre’ to the sentence, so A, B, and C are wrong. ‘But; in option D changes the intent of the sentence. E is the correct option.

VKat · Answer

Hello Team,

I was confused between c and e.
While solving, I eliminated option e because 'while' serves two meaning - simultaneous action and contrast.Although here it is clear that it should be simultaneous action, but I have seen many questions in which, although the meaning is clear in context of word 'while' , the option gets eliminated because word while has two meanings.

And as per OE, option C is wrong.
Is it wrong because it uses article 'a' before reduction ?
Because as per my understanding,
Advances in technology had led to 
-increased yield
-efficiency of labour
- profit per square
- and reduction in the amt of time in which fields are planned

All are parallel entities.

Akhilshah · Answer

Option B - had led to .....& had reduced ...can perfectly make sense & above that it is not absolute necessity to use 'and' before 'profit per square acre' as we can say had led to increased x,y,z.

Please help why option B is wrong then  GMATNinja !  KarishmaB

KarishmaB · Answer

You need to put 'and' before the last item of the list. The list is x, y and z. You cannot miss 'and' We do skip 'and' in case of an asyndeton but this sentence is not a candidate for that. Check asyndeton here: https://anaprep.com/sentence-correction-asyndeton/

By 1918, advances in tractor technology had led to increased yield,

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GMAT Sentence Correction (SC - EA only) Questions

By 1918, advances in tractor technology had led to increased yield,

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