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Over the course of the eighteenth century, the average output of ironw

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Over the course of the eighteenth century, the average output of ironw  [#permalink]

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New post Updated on: 19 Oct 2018, 04:42
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Over the course of the eighteenth century, the average output of ironwork tripled as a result of several improvements in blowing machinery and because coal replaced charcoal as the fuel used in the smelting of iron ore.


A. Over the course of the eighteenth century, the average output of ironwork tripled as a result of several improvements in blowing machinery and because coal replaced charcoal as the fuel used in the smelting of iron ore.

B. Over the course of the eighteenth century a tripling in the average output of ironwork was due to the replacement of charcoal by coal for the fuel used in the smelting of iron ore, in addition to several improvements in blowing machinery.

C. With charcoal's being replaced by coal as the fuel used in the smelting of iron ore and several improvements in blowing machinery, the average output of ironwork tripled over the eighteenth century.

D. The replacement of charcoal with coal for the fuel used in the smelting of iron ore and several improvements in blowing machinery, the average output of ironwork tripled over the eighteenth century.

E. Charcoal being replaced by coal as the fuel used in the smelting of iron ore, and several improvements in blowing machinery, which tripled the average output of ironwork over the course of the eighteenth century.

Originally posted by jerrywu on 07 Sep 2006, 10:40.
Last edited by Bunuel on 19 Oct 2018, 04:42, edited 2 times in total.
Renamed the topic and edited the question.
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Re: Over the course of the eighteenth century, the average output of ironw  [#permalink]

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New post 28 Oct 2011, 03:25
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Send me emails if you want to discuss SC with me, and the address is in the signiture.

The basic idea of my argument for choosing A is that there is an semantical ambiguity about the verbial modifier 'over the century'

I think D, E are clearly grammatically unsound.

So A B & C are left.

Now, suppose they are all grammatically correct.

In the sentence B, the problem is we are not sure about the time when 'a tripling' occurs.

Let's consider the following sentence:
#1,Over the course of the last two decades, the disintegration of the Soviet Union continued effecting the international politics.

The disintegration of Soviet Union didn't last for 20 years. What incessantly existed in the last 20 years was the effect of its disintegration. 'Over the course of the last two decades' is an adverbial modifier, and it is modifying the whole sentence, not the subject.

Back to the choice B:
Its main structure is:
over the course of 18th century (advervial modifier) a tripling (subject) was due to...(predicative).
And the adverbial is modifying the whole sentence, not the subject. So we are not sure when the 'tripling' happened.
But the author clearly wanted to tell us that 'the output of iron outwork' were incassently growing over the whole 18th century, and it tripled as a result.

So B is ambiguous.

For C

There are two ambiguous points:

1. Sentence C fails to show the causal relationship between 'the output of iron' and 'those technique improvements'.
As we can inform, the author tried to tell us the improvements of certain techniques CAUSE the tripling of iron output.
But by using 'with', the sentence C fails to tell us the logic relationship between the 'improvements of techniques' and 'tripling of iron output'

For example:
#3 I passed the exam, with the pan borrowed from my roommate.
#4 I passed the exam, by using the pan borrowed from my roommate.
#5 I passed the exam, with very little preparation

In #3, there is no causal relationship between 'pass the exam' and 'pan borrowed from my roommate'. They are just coincident.
but by #4, I claim that there is some (magical) causal relationship between 'pass the exam' and 'using the pan...'
In #5, the preposition 'with' shows a little flavor of surprise: even though I had little preparation, I passed the exam. And here, no causal relationship at all.

Back to our question. By using 'with', Sentence C only shows the coincidence of those events (like the pan and to pass the exam), not their causal relationship which the author was dying to tell us.

2. the adverbial modifier in sentence C failed tell us when those techniques improvements happed.

As I mentioned above, the adverbial modifier is modifying the sentence. In sentence C, luckily, the adverbial 'over 18 century' is clearly modifying the sentence 'the output tripled', and this is what the author wanted to say.

But it is not modifying other adverbials, i.e. 'charcoal's being replaced by coal as the fuel used in the smelting of iron ore and several improvements in blowing machinery'. Therefore, we are still not sure about when these happened.

So C is out.

Choose A.

A's structure looked wierd, because the author intenionally put the three parts together without using a comma:
1 the output tripled...
2 as a result of the improvement of...
3 and because the coal replace...
Therefore the adverbial modifier 'over the cause of the 18th century' with a comma can modify these three simultaneously, and A clearly tells us that the tripling is a tripling over the 18th century, and that the improvement of blowing technique and the coal replacement both happened some times during the 18th century.

So although A looks very artificial, it clearly shows what the author wanted to tell us
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Re: Over the course of the eighteenth century, the average output of ironw  [#permalink]

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New post 07 Sep 2006, 13:23
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A.Over the course of the eighteenth century, the average output of ironwork tripled as a result of several improvements in blowing machinery and because coal replaced charcoal as the fuel used in the smelting of iron ore.


Clear A...

B : tripling??
C : being??
D : no connection between the two phrases...
E : being??
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New post 15 Apr 2016, 04:47
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You are looking for a cause and effect in the sentence.

A. I didn't really like it but I couldn't find anything wrong.
B. A tripling ...was due to... due to is modifying tripling. Out
C. With Charcoal's - possessive, charcoal is being replaced by coal.
Proposition + Subject + Participle to describe an action.
D. The replacement ....., the average output tripled. first part has no verb.
E. which is not modifying correctly.
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Re: Over the course of the eighteenth century, the average output of  [#permalink]

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New post 15 Apr 2016, 06:03
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A. Over the course of the eighteenth century, the average output of ironwork tripled as a result of several improvements in blowing machinery and because coal replaced charcoal as the fuel used in the smelting of iron ore.

A normal construction would be - as a result of several improvements ..... and replacement of coal
In this sentence, by introducing "because" the 2nd clause (coal replaced charcoal..) is not made parallel (this seems to acceptable)

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Re: Over the course of the eighteenth century, the average output of ironw  [#permalink]

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New post 24 Jul 2016, 11:20
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In option A, are as a result of / and because Parallel?? There is nothing wrong to use it like that?

Wouldn't it be better to say it like this: "as a result of several improvements in blowing machinery and the replacement of charcoal...."??
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Re: Over the course of the eighteenth century, the average output of ironw  [#permalink]

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New post 26 Jul 2016, 19:31
jerrywu wrote:
Over the course of the eighteenth century, the average output of ironwork tripled as a result of several improvements in blowing machinery and because coal replaced charcoal as the fuel used in the smelting of iron ore.
A.Over the course of the eighteenth century, the average output of ironwork tripled as a result of several improvements in blowing machinery and because coal replaced charcoal as the fuel used in the smelting of iron ore.

B.Over the course of the eighteenth century a tripling in the average output of ironwork was due to the replacement of charcoal by coal for the fuel used in the smelting of iron ore, in addition to several improvements in blowing machinery.

C.With charcoal’s being replaced by coal as the fuel used in the smelting of iron ore and several improvements in blowing machinery, the average output of ironwork tripled over the eighteenth century.

D.The replacement of charcoal with coal for the fuel used in the smelting of iron ore and several improvements in blowing machinery, the average output of ironwork tripled over the eighteenth century.

E.Charcoal being replaced by coal as the fuel used in the smelting of iron ore, and several improvements in blowing machinery, which tripled the average output of ironwork over the course of the eighteenth century.


Meaning: Over the course of 18th century average output tripled as a result of several improvements and coal replacing charcoal
Option A is correct as it
Option B: the usage of "due to" is wrong
Option C: Usage of being is incorrect.
Option D: we need a connector between the two sentences. They cannot be joined with a comma
Option E: There is no verb in this sentence.

Correct Option: A
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Re: Over the course of the eighteenth century, the average output of ironw  [#permalink]

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New post Updated on: 24 Oct 2016, 11:13
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jerrywu wrote:
Over the course of the eighteenth century, the average output of ironwork tripled as a result of several improvements in blowing machinery and because coal replaced charcoal as the fuel used in the smelting of iron ore.

A.Over the course of the eighteenth century, the average output of ironwork tripled as a result of several improvements in blowing machinery and because coal replaced charcoal as the fuel used in the smelting of iron ore.

B.Over the course of the eighteenth century a tripling in the average output of ironwork was due to the replacement of charcoal by coal for the fuel used in the smelting of iron ore, in addition to several improvements in blowing machinery.

C.With charcoal’s being replaced by coal as the fuel used in the smelting of iron ore and several improvements in blowing machinery, the average output of ironwork tripled over the eighteenth century.

D.The replacement of charcoal with coal for the fuel used in the smelting of iron ore and several improvements in blowing machinery, the average output of ironwork tripled over the eighteenth century.

E.Charcoal being replaced by coal as the fuel used in the smelting of iron ore, and several improvements in blowing machinery, which tripled the average output of ironwork over the course of the eighteenth century.


[V] - A
- The trick in A is understanding that we have - logically- 2 reasons. Now it is true that the gmat prefers 2 elements that are structurly as well as logically the same, but in this case we cannot structure the 2 elements the same, simply becuase one is a result and the other is a reason.

[X] - B
- "a tripling" is weired, and even weireder is " a tripling was due"
- Logically we lose the focus of the sentence: in the original sentence the focus (subject) was the avg. output, in this sentence the focus (subject) is the "tripling". so this is a change in the meaning.
- "in addition" is not a parallelism marker so we have no proper parallelism.

[X] - C
- with is a prepositional . it can modify a noun entity or a verb. Notice that in this case, we lose the logical meaning of a "the reasons for the avg. increasing". this is a major change of meaning.
- the use of "Being" is incorrect, sience we are talking about a time in the past.

[Correct Usage 1]

When Being is used as a noun.
For example: Being disrespectful to elders is not an acceptable behavior.
Notice the subject here – being disrespectful to her elders

[Correct Usage 2]

When passive continuous verb tense is required to communicate the meaning.
For example:The residents of this 100-year old apartment complex are being evacuated because of structural instability of the building.
Notice the verb tense here – are being evacuated – present continuous written in passive voice.

X - [D]
- The 1st phrase in this optional answer is not properly connected to the 1st clause.
- We have ambiguity problem: this 2 parallel object in the list created with "and" could have several logical options:
* "The replacement of charcoal with coal for the fuel used in [the smelting] of iron ore and [several improvements in blowing machinery]"
* "The replacement of charcoal with [coal] for the fuel used in the smelting of iron ore and [several improvements in blowing machinery]"
* "[The replacement of charcoal] with coal for the fuel used in the smelting of iron ore and [several improvements in blowing machinery]"

X - [E]
- "being replaced" is not a verb
- this is the wrong use of "being"
- we have no verb for charcoal
- ambiguity problem: [several improvements] in blowing [machinery], which tripled the average output
* both the improvments and the machinery could have tripled the output.

Originally posted by AlexGenkins1234 on 04 Oct 2016, 07:04.
Last edited by AlexGenkins1234 on 24 Oct 2016, 11:13, edited 1 time in total.
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Re: Over the course of the eighteenth century, the average output of ironw  [#permalink]

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Over the course of the eighteenth century, the average output of ironwork tripled as a result of several improvements in blowing machinery and because coal replaced charcoal as the fuel used in the smelting of iron ore.

A. Over the course of the eighteenth century, the average output of ironwork tripled as a result of several improvements in blowing machinery and because coal replaced charcoal as the fuel used in the smelting of iron ore. -- Perhaps the choice that comes nearest to the best with the introductory prepositional phrase duly followed by the subject and its action of tripling.

B. Over the course of the eighteenth century, a tripling in the average output of ironwork was due to the replacement of charcoal by coal for the fuel used in the smelting of iron ore, in addition to several improvements in blowing machinery. --- The prepositional introducer is wrongly modified by a tripling while it should modify the subject 'the average output'.

C.With charcoal's being replaced by coal as the fuel used in the smelting of iron ore and several improvements in blowing machinery, the average output of ironwork tripled over the eighteenth century. ---Who is replacing the coal should be placed next to the comma after machinery. Faulty modification

D.The replacement of charcoal with coal for the fuel used in the smelting of iron ore and several improvements in blowing machinery, the average output of ironwork tripled over the eighteenth century. -- No connect between the introducer and the main clause as many have pointed out.

E. Charcoal being replaced by coal as the fuel used in the smelting of iron ore, and several improvements in blowing machinery, which tripled the average output of ironwork over the course of the eighteenth century. --- A fragment.
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Re: Over the course of the eighteenth century, the average output of ironw  [#permalink]

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New post 19 Nov 2017, 21:31
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jerrywu wrote:
Over the course of the eighteenth century, the average output of ironwork tripled as a result of several improvements in blowing machinery and because coal replaced charcoal as the fuel used in the smelting of iron ore.
A.Over the course of the eighteenth century, the average output of ironwork tripled as a result of several improvements in blowing machinery and because coal replaced charcoal as the fuel used in the smelting of iron ore.

B.Over the course of the eighteenth century a tripling in the average output of ironwork was due to the replacement of charcoal by coal for the fuel used in the smelting of iron ore, in addition to several improvements in blowing machinery.

C.With charcoal's being replaced by coal as the fuel used in the smelting of iron ore and several improvements in blowing machinery, the average output of ironwork tripled over the eighteenth century.

D.The replacement of charcoal with coal for the fuel used in the smelting of iron ore and several improvements in blowing machinery, the average output of ironwork tripled over the eighteenth century.

E.Charcoal being replaced by coal as the fuel used in the smelting of iron ore, and several improvements in blowing machinery, which tripled the average output of ironwork over the course of the eighteenth century.


Responding to a pm:

Between (A) and (B), (A) clearly explains the meaning.

Over the course of the eighteenth century, the average output of ironwork tripled as a result of several improvements in blowing machinery and because coal replaced charcoal as the fuel used in the smelting of iron ore.

The output tripled ...
When? over the course of the century
Why? as a result of several improvements in blowing machinery and because coal replaced charcoal as the fuel used in the smelting of iron ore (2 reasons)
The 2 reasons are joined with an "and" and act as adverbs. There is no parallelism issue here.

Look at (B) now -

A tripling was ...
When? over the course of the century

What does that mean? "was" indicates a point in time. But "over the course ..." indicates a period of time.
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New post 18 Dec 2017, 08:14
I chose B. Why B is wrong? Thanks!
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Re: Over the course of the eighteenth century, the average output of  [#permalink]

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New post 18 Dec 2017, 10:48
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septwibowo wrote:
I chose B. Why B is wrong? Thanks!


SC is as much about finding grammatical errors as it is about Meaning.

B. The structure of B
Over a period of time , a tripling ... was due to .... -----> What's the core verb? 'Was'? Horrible !

Just because 'due to' is used with nouns, the author changed the verb 'tripled' to 'tripling was'. This kind of structure has not only concealed the main action of the sentence incorrectly but also introduced an unidiomatic phrase - tripling in the average.

The structure of A is far better than that of B-
A. Over the course of the eighteenth century, the average output of ironwork tripled....... - the heart of the sentence is perfectly retained, following the reasons of why it did. Correct
-A-
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Re: Over the course of the eighteenth century, the average output of  [#permalink]

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New post 25 Dec 2017, 05:09
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TaN1213 wrote:
septwibowo wrote:
I chose B. Why B is wrong? Thanks!


SC is as much about finding grammatical errors as it is about Meaning.

B. The structure of B
Over a period of time , a tripling ... was due to .... -----> What's the core verb? 'Was'? Horrible !

Just because 'due to' is used with nouns, the author changed the verb 'tripled' to 'tripling was'. This kind of structure has not only concealed the main action of the sentence incorrectly but also introduced an unidiomatic phrase - tripling in the average.

The structure of A is far better than that of B-
A. Over the course of the eighteenth century, the average output of ironwork tripled....... - the heart of the sentence is perfectly retained, following the reasons of why it did. Correct
-A-


Thank you for your explanation TaN1213.

However, I think that construction "was due to" is fine.
Magoosh gave example in its course : "The delay was due to rain" and that is perfectly fine : due to modify the delay.

Here, in (B), :

a tripling in the average output of ironwork was due to the replacement of charcoal by coal for the fuel used in the smelting of iron ore, in addition to several improvements in blowing machinery.


- "Due to" modify noun phrase : "a tripling in the average output of ironwork"
- A tripling was due to X, in addition Y.

Wdyt? mikemcgarry, need your clarification here :-)
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New post 26 Dec 2017, 11:06
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septwibowo wrote:
Thank you for your explanation TaN1213.

However, I think that construction "was due to" is fine.
Magoosh gave example in its course : "The delay was due to rain" and that is perfectly fine : due to modify the delay.

Here, in (B), :

a tripling in the average output of ironwork was due to the replacement of charcoal by coal for the fuel used in the smelting of iron ore, in addition to several improvements in blowing machinery.


- "Due to" modify noun phrase : "a tripling in the average output of ironwork"
- A tripling was due to X, in addition Y.

Wdyt? mikemcgarry, need your clarification here :-)

Dear septwibowo,

I have many things to say in response, my friend. :-)

First of all, I want to acknowledge TaN1213 for an intelligent and thoughtful response. I completely agree with TaN1213.

Next, septwibowo: you got a brilliant explanation from TaN1213 and, rather than learning the deep point that this user presented, you presented a counterargument. One of the deepest questions any student can ask himself is, "Do I want to be right or do I want to learn as much as I can?" You see, it's a paradox: of course on test day, you primarily want to be right (although you can learn even there), but the way to get to that is by disattaching from a need to be right while you are in the role of a student, because being holding to a position of being right can prevent you from picking up a new subtlety.

In this GMAT SC problem, choice (B) is precisely the kind of incorrect answer choice that acts as a trap for non-native speakers: it's 100% grammatically correct but wrong. Virtually all the high level SC questions have at least one such choice. This is a classic predictable trap and you fell into it.

Yes, the "is due to" construction in (B) is 100% grammatically correct. There's absolutely no ambiguity about that: you and I and TaN1213 are in full agreement about that. It's true and also completely besides the point. Choice (B) is 100% grammatically correct but it's still wrong. That's the piece you are missing: you are focused on the grammar and missed that TaN1213's brilliant response was addressing other aspects of the sentence beyond the grammar.

The GMAT SC is NOT primarily a test of grammar. On the GMAT SC, grammar & logic & rhetoric all combine to support meaning.

The principles of good rhetorical construction can be hard for non-native speakers to appreciate, because much of it is intuitive--it's about the "feel" of the sentence. Here's one principle that I can articulate: when a sentence is focused on a main action, this sentence usually will be phrased in the most direct and powerful way when that main action is the main verb of the sentence.

Choice (A) follows this principle fully. Choice (A) is not only grammatically correct but also direct, clear, and powerful. Like almost all correct answers on the GMAT SC, it's an exceptionally well-crafted sentence.

Choice (B) is 100% grammatically correct but it's an embarrassingly awkward and punchless sentence. In particular, the main action of the sentence, "tripling," is congealed as a gerund subject, and the sentence is organized so that a complete non-action verb, "is," winds up as the main verb of the sentence. Any well-read native speaker instantly would recognize this as a poorly written section. The fact that you selected choice (B) as correct and were willing to defend it should tell you a great deal about the progress you still have to make.

Grammar has a lot of rules, although many of the rules have exceptions. Rhetoric doesn't have many rules--it's more intuition-based. A non-native speaker can develop this intuition by cultivating a rigorous habit of reading. See:
How to Improve Your GMAT Verbal Score

Does all this make sense?
Mike :-)
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Re: Over the course of the eighteenth century, the average output of  [#permalink]

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New post 28 Sep 2018, 12:14
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I somehow feel A is not the correct answer because

1. as a result of several improvements in blowing machinery (A phrase)
2. because coal replaced charcoal as the fuel used in the smelting of iron ore (A clause)

Both don't seem parallel
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Over the course of the eighteenth century, the average output of  [#permalink]

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New post 28 Sep 2018, 16:46
Prateek176 wrote:
I somehow feel A is not the correct answer because

1. as a result of several improvements in blowing machinery (A phrase)
2. because coal replaced charcoal as the fuel used in the smelting of iron ore (A clause)

Both don't seem parallel

The only situations in which wording alone REALLY affects whether structures are considered parallel are situations in which gerunds or infinitives are used in lists.

While, for instance, "to swim" and "swimming" could both function as nouns, the GMAT, and most writers, prefer that the two forms not be mixed.

So the GMAT would not prefer the following:

In summer, the vacationers like to swim and going to the beach.

It would prefer either of the following:

In summer, the vacationers like to swim and to go to the beach.

In summer, the vacationers like swimming and going to the beach.


However, the wording in most cases does not have to be so exactly parallel. Consider the following, which would be fine on the GMAT:

The car is shiny and well kept.

While "shiny" is an adjective and "kept" is a participle, since they modify the noun "car" in similar ways, adjectivally, the structure is considered parallel.

Let's now consider choice (A).

(A) Over the course of the eighteenth century, the average output of ironwork tripled as a result of several improvements in blowing machinery and because coal replaced charcoal as the fuel used in the smelting of iron ore.

We have two modifiers modifying "tripled":

as a result of several improvements in blowing machinery

because coal replaced charcoal as the fuel used in the smelting of iron ore


"as a result of several improvements in blowing machinery" is a phrase that serves as an adverb.

"because coal replaced charcoal as the fuel used in the smelting of iron ore" is an adverb clause.

So, even though the two structures don't look parallel, they both function adverbially and, thus, are parallel in a logical sense. So, choice (A) is solid.
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