The primary catalyst fueling the rapid spread of wind farms across the

Question

The primary catalyst fueling the rapid spread of wind farms across the country – from offshore platforms along the coasts through the vast deserts and plains – has been a combination of federal tax incentives and state mandates requiring utilities to raise renewable power to increasing percentages of their overall energy production.

Primary catalyst is the subject and its verb is 'has been'.
'Requiring' is modifying the closest noun i.e. state mandates.
'Their' unambiguously refers to 'federal tax incentives and state mandates'.

(A) has been a combination of federal tax incentives and state mandates requiring utilities to raise renewable power to increasing percentages of their

(B) have been combinations of federal tax incentives and state mandates requiring utilities to raise renewable power to increasing percentages of their

(C) has been a combination of federal tax incentives and state mandates that require utilities to raise renewable power to an increasing percentage of its

(D) have been a combination of federal tax incentives and state mandates that require utilities to raise renewable power to increasing percentages of their

(E) has been a combination of federal tax incentives and of state mandates requiring utilities to raise renewable power to increasing percentages of its

daagh · Accepted Answer

NKS 
'Their' will refer to the utilities. 'Utilities' means the companies that are generating power. They may be thermal power companies or hydroelectric companies, or nuclear companies. These companies are being compelled by the government to increase the percentage of renewable power in their overall production and wind farms are one of the prime contributors of renewable power generation.

Shiv2016 · Answer

The primary catalyst fueling the rapid spread of wind farms across the country – from offshore platforms along the coasts through the vast deserts and plains – has been a combination of federal tax incentives and state mandates requiring utilities to raise renewable power to increasing percentages of their overall energy production.

Primary catalyst is the subject and its verb is 'has been'.
'Requiring' is modifying the closest noun i.e. state mandates.
'Their' unambiguously refers to 'federal tax incentives and state mandates'.

Primary catalyst is the subject and its verb is 'has been'.
'Requiring' is modifying the closest noun i.e. state mandates.
'Their' unambiguously refers to 'federal tax incentives and state mandates'.

nazgull · Answer

I beg to differ from your explanation. 
'Requiring' is modifying the closest noun i.e.  state mandates.  combination.
- of federal tax incentives and state mandates  is a prepositional modifier that is modifying the noun 'combination'
'Their'  unambiguously refers to 'federal tax incentives and state mandates'.  refers to the noun 'utilities'

max0010 · Answer

"requiring" in the original sentence modifies "combination" and not the closest noun. How can "federal tax incentives" require anything? The intended meaning is, a combination of federal tax incentives and something else (state mandates ... energy production) has caused the rapid spread of wind farms.

The logical antecedent of "Their" is "utilities" and not to "'federal tax incentives and state mandates'". How "federal tax incentives and state mandates" have energy production?

The correct answer should be E.

What is source of this question, also, can you please provide the OE?

RMD007 · Answer

Though not an expert, my two cents for answer A.

1. Requiring modifies closest noun i.e. state mandates 
2. Antecedent for theirs is - wind farms

The Subject here is - Primary catalyst - singular. Choice B and D are out.

C. has been a combination of federal tax incentives and state mandates that require utilities to raise renewable power to an increasing percentage of  its   --> Here we are referring to wind farms so we require plural pronoun.

E. has been a combination of federal tax incentives and  of  state mandates requiring utilities to raise renewable power to increasing percentages of their

eddy8700 · Answer

The primary catalyst fueling the rapid spread of wind farms across the country – from offshore platforms along the coasts through the vast deserts and plains – has been a combination of federal tax incentives and state mandates requiring utilities to raise renewable power to increasing percentages of their overall energy production.

Primary catalyst is the subject and its verb is 'has been'.
'Requiring' is modifying the closest noun i.e. state mandates.
'Their' unambiguously refers to 'federal tax incentives and state mandates'.

A. has been a combination of federal tax incentives and state mandates requiring utilities to raise renewable power to increasing percentages of their 
B. have been combinations of federal tax incentives and state mandates requiring utilities to raise renewable power to increasing percentages of their 
C. has been a combination of federal tax incentives and state mandates that require utilities to raise renewable power to an increasing percentage of its 
D. have been a combination of federal tax incentives and state mandates that require utilities to raise renewable power to increasing percentages of their 
E. has been a combination of federal tax incentives and of state mandates requiring utilities to raise renewable power to increasing percentages of their

Lets apply vertical split to narrow down the choices
the subject of the sentence is primary catalyst singular
so has is the correct form here
B and D instant elimination
In C 
combination of..........that require
combination singular hence requires is correct verb
So C is out

IN A and E
X and Y
X or Y
these are open parallelism markers
that means any preposition before X also applies to Y
of X and Y is correct rather than using of X and of Y
so A is the best answer

techiesam · Answer

daagh

Sir Don't you think we need a comma before the gerund requiring in option A ?It is logical that requiring is modifying both  federal tax incentives and state mandates

daagh · Answer

The primary catalyst fueling the rapid spread of wind farms across the country – from offshore platforms along the coasts through the vast deserts and plains – has been a combination of federal tax incentives and state mandates requiring utilities to raise renewable power to increasing percentages of their overall energy production.

Primary catalyst is the subject and its verb is 'has been'.
'Requiring' is modifying the closest noun i.e. state mandates.
'Their' unambiguously refers to 'federal tax incentives and state mandates'.

I don't think so, techie. Let us delve into the real meaning of the text. The wind farms are growing in number. The reasons are: 
1. persuasive incentives and 
2. statutory mandates(incidentally a plural noun here) that the utilities under question must increase their share of renewable energy in the overall production. ( While incentives may not impose penalties, mandates may well institute penalties if not complied with). So the 'requiring' part is clearly referring to the mandates alone and not to the combination. Both are disparate
Now can you see, why we cannot afford to put a comma before the adverbial participle 'requiring'?

harshanitr · Answer

Here there are two subject-verb agreements.
1) primary catalyst (singular subject) should be followed by 'has'.
2) Utilities (plural suject) should be followed by 'their'.
So we are left with only option A &E.

now consider option E. It has improper usage "combination of federal tax incentives and of state mandates" which is incorrect. So The correct option is  A

nks2611 · Answer

hello,
 Daagh sir ,
 after going through your explanation i got to know why we can't have a comma before requiring, because if we do so then subject will not be clear for the 2nd part it could also 'The primary catalyst fueling the rapid spread' . so the comma will be wrong .
but still could you please clarify my doubt -
that pronoun their refers to which noun = wind firms or utilities ?

please correct me .
many thanks

dabhishek87 · Answer

The primary catalyst fueling the rapid spread of wind farms across the country – from offshore platforms along the coasts through the vast deserts and plains – has been a combination of federal tax incentives and state mandates requiring utilities to raise renewable power to increasing percentages of their overall energy production.

Primary catalyst is the subject and its verb is 'has been'.
'Requiring' is modifying the closest noun i.e. state mandates.
'Their' unambiguously refers to 'federal tax incentives and state mandates'.

A.  has been  a combination of federal tax incentives and state mandates requiring  utilities  to raise renewable power to increasing percentages of  their  
B.  have been  combinations of federal tax incentives and state mandates requiring utilities to raise renewable power to increasing percentages of their 
C.  has been  a combination of federal tax incentives and state mandates that require utilities to raise renewable power to an increasing percentage of  its  
D.  have been  a combination of federal tax incentives and state mandates that require utilities to raise renewable power to increasing percentages of their 
E.  has been  a combination of federal tax incentives and  of  state mandates requiring utilities to raise renewable power to increasing percentages of their

skysailor · Answer

A. has been a combination of federal tax incentives and state mandates requiring utilities to raise renewable power to increasing percentages of their -  correct 
B. have been combinations of federal tax incentives and state mandates requiring utilities to raise renewable power to increasing percentages of their -  "have been" is wrong. It modifies "catalyst", which is singular.
 
C. has been a combination of federal tax incentives and state mandates that require utilities to raise renewable power to an increasing percentage of its -  "its" is wrong since "utilities" is plural 
D. have been a combination of federal tax incentives and state mandates that require utilities to raise renewable power to increasing percentages of their -  "have been" is wrong. It modifies "catalyst", which is singular. 
E. has been a combination of federal tax incentives and of state mandates requiring utilities to raise renewable power to increasing percentages of their -  "combination of federal tax incentives and of state mandates" no need for "of" after the "and" here

daagh · Answer

The primary catalyst fueling the rapid spread of wind farms across the country – from offshore platforms along the coasts through the vast deserts and plains – has been a combination of federal tax incentives and state mandates requiring utilities to raise renewable power to increasing percentages of their overall energy production.

Primary catalyst is the subject and its verb is 'has been'.
'Requiring' is modifying the closest noun i.e. state mandates.
'Their' unambiguously refers to 'federal tax incentives and state mandates'.

A. has been a combination of federal tax incentives and state mandates requiring utilities to increase the percentage of renewable power in their ----  "a combination- has been', "utilities-their" --- 'their' refers to the utilities --correct 
 
B. have been combinations of federal tax incentives and state mandates requiring utilities to increase the percentage of renewable power in their ----  "a combination - have been "- SV number error

C. has been a combination of federal tax incentives and state mandates that require utilities to increase the percentage of renewable power in its ---  'utilities-its' --- pronoun number error

D. have been a combination of federal tax incentives and state mandates that require utilities to increase the percentage of renewable power in their ---  'a combination --- have been' - S V number error as in B. 
 
E. has been a combination of federal tax incentives and of state mandates requiring utilities to increase the percentage of renewable power in its ----  'utilities -- its' -pronoun number error

elegantm · Answer

The primary catalyst fueling the rapid spread of wind farms across the country – from offshore platforms along the coasts to the vast deserts and plains –  has been a combination of federal tax incentives and state mandates requiring utilities to increase the percentage of renewable power in their  overall energy production portfolio.
A. has been a combination of federal tax incentives and state mandates requiring utilities to increase the percentage of renewable power in their
 Correct 
B.  have  been  combinations  of federal tax incentives and state mandates requiring utilities to increase the percentage of renewable power in their
 Singular verb "HAS" should be used for singular noun "Catalyst". Hence Incorrect 
C. has been a combination of federal tax incentives and state mandates that require utilities to increase the percentage of renewable power in  its 
 Plural pronoun "THEIR" should be used for Plural antecedent "UTILITIES". Hence Incorrect 
D.  have  been a combination of federal tax incentives and state mandates that require utilities to increase the percentage of renewable power in their
 Singular verb "HAS" should be used for singular noun "Catalyst". Hence Incorrect 
E. has been a combination of federal tax incentives and  of  state mandates requiring utilities to increase the percentage of renewable power in its
 Plural pronoun "THEIR" should be used for Plural antecedent "UTILITIES". Hence Incorrect

kunalsinghNS · Answer

Option A fits the best for the above mentioned question.

but i have a doubt - shouldn't there be a "comma" before "requiring" ?

experts please help.

Leo8 · Answer

The primary catalyst fueling the rapid spread of wind farms across the country – from offshore platforms along the coasts through the vast deserts and plains – has been a combination of federal tax incentives and state mandates requiring utilities to raise renewable power to increasing percentages of their overall energy production.

Primary catalyst is the subject and its verb is 'has been'.
'Requiring' is modifying the closest noun i.e. state mandates.
'Their' unambiguously refers to 'federal tax incentives and state mandates'.

The primary catalyst is a singular subject which requires singular verb.

answers can be divided into two categories
 has vs have & its vs their

we need has as a verb for primary catalyst and plural pronoun to refer plural antecedent utilities

no option other than A has the correct combination : Hence A

A. has been a combination of federal tax incentives and state mandates requiring utilities to increase the percentage of renewable power in their

B.  have  been combinations of federal tax incentives and state mandates requiring utilities to increase the percentage of renewable power in their

C. has been a combination of federal tax incentives and state mandates that require utilities to increase the percentage of renewable power in  its

D.  have  been a combination of federal tax incentives and state mandates that require utilities to increase the percentage of renewable power in their

E. has been a combination of federal tax incentives and of state mandates requiring utilities to increase the percentage of renewable power in  its

MaximD · Answer

It is C i believe!
Because,

First we have 'has' or 'have'. Since it needs to refer to 'the primary catalyst' it should be has, as it is singular.
So, B and D are out.
Then we have 'its' or 'their' at the end of the sentence. I see some people who say its would refer to utilities. But the sentence states 'its'/ 'their' energy production portfolio. Since when do utilities have a portfolio? Doesn't its or their refer to the country? With regard to this perspective, the answers with 'their' are out.
Then, we only have C and E left. 
Mandate is bossy a verb. So, 'that' should follow mandate. And C has this construction!

Therefore, i choose C.

daagh · Answer

kunalsingh1991 wrote

When a comma is before 'requiring', then the 'requiring' will modify the primary catalyst as if the catalyst is requiring the utilities to do something. On the contrary, it is the government mandates that stipulate the conditions. Thus, the meaning will substantially change by the intrusion of the comma as suggested.

origen87 · Answer

Not an expert here but my two cents
Option A in full with comma
A. The primary catalyst fueling the rapid spread of wind farms across the country has been a combination of federal tax incentives and state mandates, requiring utilities to increase the percentage of renewable power in their overall energy production portfolio.

Now requiring has to make sense with the complete sentence and with the subject. The primary catalyst requiring.... this doesnt make sense...
without comma, requiring refers to 'combination of federal tax incentives and state mandates' and therefore makes sense.

Experts may please pitch in.

The primary catalyst fueling the rapid spread of wind farms across the

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The primary catalyst fueling the rapid spread of wind farms across the

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