Prospecting for gold during the California gold rush was a relatively

I did not understand the meaning of the sentence and hence picked (B), even though I did not like that option. But thought it is best among the lot until I saw the OA.

Prospecting for gold during the California gold rush was a relatively easy task, because of erosion, prehistoric glacier movement, and ancient, gold-bearing riverbeds thrust to the surface by volcanic activity put gold literally within reach for anybody with a pan or shovel.

A.) because of erosion, prehistoric glacier movement, and ancient, gold-bearing riverbeds thrust to the surface by volcanic activity put gold literally within reach for - incorrect

B.) because of erosion, prehistoric glacier movement, and volcanic activity that thrust ancient, gold-bearing riverbeds to the surface, and putting gold literally within reach of -

C.) owing to erosion, prehistoric glacier movement, and volcanic activity that had thrust ancient, gold-bearing riverbeds to the surface, and putting gold literally within reach of - incorrect

D.) since erosion, prehistoric glacier movement, and volcanic activity that thrust ancient, gold-bearing riverbeds to the surface, putting gold literally within reach for - incorrect

E.) since erosion, prehistoric glacier movement, and ancient, gold-bearing riverbeds thrust to the surface by volcanic activity put gold literally within reach of - correct

[quote="burnttwinky"]Prospecting for gold during the California gold rush was a relatively easy task, because of erosion, prehistoric glacier movement, and ancient, gold-bearing riverbeds thrust to the surface by volcanic activity put gold literally within reach for anybody with a pan or shovel.

A.) Same

B.) because of erosion, prehistoric glacier movement, and volcanic activity that thrust ancient, gold-bearing riverbeds to the surface, and putting gold literally within reach of

C.) owing to erosion, prehistoric glacier movement, and volcanic activity that had thrust ancient, gold-bearing riverbeds to the surface, and putting gold literally within reach of

D.) since erosion, prehistoric glacier movement, and volcanic activity that thrust ancient, gold-bearing riverbeds to the surface, putting gold literally within reach for

E.) since erosion, prehistoric glacier movement, and ancient, gold-bearing riverbeds thrust to the surface by volcanic activity put gold literally within reach of

A & B are incorrect : "because" is signifying cause and effect which is not the case. Also because of is unidiomatic and generally avoided in GMAT.
C = putting is Ving form and incorrect here : also had signifies 2 actions in the past, and there are no 2 actions.
D = putting is incorrect : reach for is unidiomatic
E = correct

Prospecting for gold during the California gold rush was a relatively easy task, because of erosion, prehistoric glacier movement, and ancient, gold-bearing riverbeds thrust to the surface by volcanic activity put gold literally within reach for anybody with a pan or shovel.

First of all, Because of -> takes noun or noun phrase so because of cannot take a clause.

For example

Match was delayed because of heavy rain -> Correct
Match was delayed because of rain was heavy -> Incorrect


A.) because of erosion, prehistoric glacier movement, and ancient, gold-bearing riverbeds thrust to the surface by volcanic activity put gold literally within reach for

"Because of" takes noun or noun phrase

B.) because of erosion, prehistoric glacier movement, and volcanic activity that thrust ancient, gold-bearing riverbeds to the surface, and putting gold literally within reach of

And putting should be parallel to something. It cannot be parallel to "that trust" as that is a clause. Hence "and putting" is not structurally correct

C.) owing to erosion, prehistoric glacier movement, and volcanic activity that had thrust ancient, gold-bearing riverbeds to the surface, and putting gold literally within reach of

Past perfect tense is not required here. Even if we use past perfect, the dependent event should have "simple past" which is not present and hence the usage is wrong.

D.) since erosion, prehistoric glacier movement, and volcanic activity that thrust ancient, gold-bearing riverbeds to the surface, putting gold literally within reach for

Structurally, the sentence is fine. We have a clause and then we have a verb+ing modifier but meaning doesn't come out properly.

As per the sentence "that thrust ancient, gold-bearing riverbeds to the surface, putting gold literally within reach for" -> That refers to "Volcanic activity" so as per verb+ing modifier, the subject of the previous clause attaches to the action of putting the gold within reach. But as per meaning of the sentence
All the three "Erosion, prehistoric glacier movement and volcanic activity has put gold within reach of anybody."

E.) since erosion, prehistoric glacier movement, and ancient, gold-bearing riverbeds thrust to the surface by volcanic activity put gold literally within reach of
- Correct.

Normally, I don't eliminate options based on idioms as GMAT is moving away from idiom testing. But "reach of" is more preferred than "Reach for".

awesome explanation by e-gmat (always clear).
lets apply our 3-step process to solve this one.

Meaning: This sentence shows a cause and effect.

Effect = prospecting for gold was easy during gold rush
Cause = This happened because the factors below caused the gold to come within reach of people

Erosion
Glacier movement
Riverbeds

Error Analysis:

Error 1: SV - Must Exist

There are two clauses in this sentence:

Prospecting for gold during the California gold rush was a relatively easy task,
Because of erosion, prehistoric glacier movement, and ancient, gold-bearing riverbeds thrust to the surface by volcanic activity put gold literally within reach for anybody with a pan or shovel.

SV Pair in Clause 1 = Prospecting – was
SV Pair in Clause 2 = no subject – put
Here is why:

Clause 2 (simplified form) = Because of A, B, and C put gold...The presence of "of" after because implies that A, B, and C cannot be the subject for the verb - put because these elements fall in prepositional phrase. This can be corrected by any of the following edits:
Because A, B, and C put gold...
Because of A, B, and C gold was put...(Change active voice to passive voice).
My preference is the first edit since it is more precise than the second edit.

Error 2: reach for is not idiomatic usage. It should be reach of.
Lets simplify the idiom usage:
The can is in the reach of the child.
The can is in the reach for the child.

Clearly reach of is better than reach for.

Note that "thrust to the surface..." is a verb-ed modifier that modifies the preceding noun - riverbeds.

POE:
Choice B:

because of erosion, prehistoric glacier movement, and volcanic activity that thrust ancient, gold-bearing riverbeds to the surface, and putting gold literally within reach of

Error 1: Changes intended meaning
This choice changes the list. The list per this choice is as follows:
Effect = prospecting for gold was easy during gold rush
Cause = There is a list of reasons:
Erosion
Glacier movement
volcanic activity
that thrust riverbeds to the surface
and putting gold within reach of people
This choice now implies that erosion, glacier movement and volcanic activity - 3 factors thrust riverbeds to the surface. This is different from the intended meaning - volcanic activity thrust riverbeds to the surface.

Furthermore, this choice implies that prospecting for gold was easy because riverbeds were thrust to the surface and gold was put within the reach. This is again not the intended meaning - prospecting for gold was easy because gold was within reach of people because of three factors - erosion, glaciers, and riverbeds.

Error 2 - List is not grammatically parallel.
Because of
A, B, and C that did something
putting...

Choice C: owing to erosion, prehistoric glacier movement, and volcanic activity that had thrust ancient, gold-bearing riverbeds to the surface, and putting gold literally within reach of

This choice also has similar errors as Choice B does.
Additionally, as you indicated "had thrust" is incorrect. It should be simple past tense.
As with choice B, even if we replaced putting with put, it will still contain both errors.

Choice D: since erosion, prehistoric glacier movement, and volcanic activity that thrust ancient, gold-bearing riverbeds to the surface, putting gold literally within reach for
Error 1: Subject Verb Must Exist
The subject - erosion, glacier movement, and volcanic activity has no verb

Error 2: Changes intended meaning.
Notice again that the list has been changed. The third element is now volcanic activity instead of riverbeds.

Error 3: reach for is idiomatically incorrect

Choice E: Correct answer

Hi GMATNinja, GMATNinjaTwo

I really didn't get how option E is correct. According to previous posts, there 3 things parallel in Option E

X = erosion
Y = prehistoric glacier movement
Z = ancient

As X and Y are nouns, Z also has to be a noun to be parallel

But here "ancient" is used an adjective. How can this be parallel? I'm really confused with the parallelism here.

Hey pikolo2510 ,

Z in your parallel structure is "ancient, gold-bearing riverbeds thrust to the surface" rather than just ancient. Ancient is an adjective modifying the riverbeds.

Hence, E is correct.

Does that make sense?

Hey abhimahna,

Thanks for your reply. But I still have the following doubts

1. If thats the case, why do we have a comma between "ancient" and "gold bearing-riverbeds" . It is confusing to find the parallel structure with the comma.

2. Also, the part after "gold bearing riverbeds" - what is it describing? "Gold bearing riverbeds" OR all the three parallel parts? The comma again confuses what is being modified

Hey pikolo2510 ,

I read the sentence again and here is what I found.

We are saying some task is easy because Clause.

Here Clause is "since erosion, prehistoric glacier movement, and ancient, gold-bearing riverbeds thrust to the surface by volcanic activity put gold literally within reach of..."

Now, Look at the Subject and Verb in the clause.

Our Subject is "erosion, prehistoric glacier movement, and ancient, gold-bearing riverbeds thrust to the surface by volcanic activity"

Verb is "put".

Now, if I look at the subject, we have a conjunction "and" and the construction X, Y and Z.

X: erosion
Y: prehistoric glacier movement
Z: ancient, gold-bearing riverbeds thrust to the surface by volcanic activity

All the blue highlighted are actually the point of comparisons and other information is just the modifier.

Now, please note that whenever you are adding too many adjectives to a noun, it is okay to have a comma between those objectives.

So, Our very first adjective is "gold-bearing" and the 2nd adjective is "ancient". Both of these adjectives are referring to the riverbeds thrust.

If you don't put a comma between the two, the adjective "ancient" will act as an adjective of "gold-bearing". So, basically it will act as an adjective of an adjective. But this is not the intended meaning of the sentence. We are not saying Gold bearing was ancient. Rather, we are saying the thrust was ancient. Hence, a comma is very much required here.

Does that make sense?

Be careful not to be TOO rigid in your analysis of the parallelism. Consider these two silly sentences:

• For breakfast, I ate eggs and ham. --> fine, since "eggs" and "ham" are two tasty, parallel nouns
• For breakfast, I ate eggs and green ham. --> technically, we have "I ate noun and adjective noun", but there's really no problem here: these are two foods (nouns), and we just happened to describe one of them in more detail with an adjective ("green ham")

So look a little bit more closely at Z: it doesn't just say "ancient", it says "ancient, gold-bearing riverbeds." As the ever-wise abhimahna pointed out, "ancient" and "gold-bearing" are just modifiers (specifically adjectives), and the essence is still that we have a noun: "riverbeds." So we're all good on the parallelism.

I hope this helps!

Can anyone explain the role of thrust and put in the correct answer choice?
Which one is the main verb between the two ?

What makes this distinction tricky is that “thrust” can function as both a verb and a modifier. Take some silly examples: “Knowing she didn’t have much time to dispose of the evidence, Amy thrust her shovel into the ground with great force and efficiency.” Here “thrust” is a verb – it’s the action Amy is performing.

But “thrust” can also be used as a modifier. “The shovel thrust into the ground broke when it collided with the surprisingly shallow coffin.” Now “thrust” is a modifier describing the shovel. Which shovel? The one thrust into the ground. It’s the presence of the verb “broke” that helps clue us in to the fact that “thrust” plays a different role here.

The OA for this question is more like the second of the two above examples.


“Thrust” is a modifier describing the riverbeds. Which “riverbeds?” The ones thrust to the surface by volcanic activity.

“Put” is the main verb of the sentence, the action performed by erosion, glacier movement, and those aforementioned riverbeds.

I hope that helps!

The first part of the sentence is the main clause, there should not be a comma to separate it from the dependent clause. Why a comma before "since?"

daagh, GMATNinja, parker

Excellent question! If you're a usage guide nerd, you may at some point have come across the "rule" that if you begin a sentence with an independent clause and follow it with a dependent clause, you don't use a comma. For example, "Dave likes to watch Frozen with his children because he prefers the sound of his children singing to the sound of his children screaming." (But not by much.) There's no need for a comma before "because" here, as it's introducing a dependent clause that provides information about the main one.

However, this is less a rule than a convention, and it's a good reminder that we don't want to be too rigid about applying "rules" in Sentence Correction, particularly when it comes to comma usage, which is ultimately left to the discretion of the writer.

In some cases, a comma, though not technically required, can help clarify the meaning of the sentence. Consider (E) without the comma: "Prospecting for gold during the California gold rush was a relatively easy task since erosion..." The confusion comes from the fact that "since" can be used two ways. It can mean 1) "because" or 2) "from the time when."

Without the comma, the sentence seems to communicate that prospecting for gold was easy since the time of erosion, as opposed to the intended meaning, which is that prospecting was easy because of erosion. The comma makes this distinction clearer.

In other words, there's no definitive grammar rule here - it all comes down to meaning and clarity. And for whatever it's worth, the GMAT doesn't generally waste its time testing comma usage. A little bit more on that issue can be found in this video on GMAT punctuation.

I hope that helps!

The answer is E in my view.

Because of and owing to cannot introduce a clause. Why? Because of and owing to or due to are compound prepositions and their structure is: because of/owing to + noun/gerund. They are used purely as modifiers and the nouns associated with them should be objects rather than subjects of verbs. The form because of/owing to/due to + noun + participle is unacceptable on the GMAT. Based on this, we can eliminate A, B, and C.
A is incorrect because because of introduces a clause and this is unacceptable.
B is incorrect because because of followed by three nouns X: erosion, Y: prehistoric glacier movement, and Z: volcanic activity that thrust A: ancient, gold-bearing riverbeds to the surface, and B: putting gold literally within reach of everyone. X,Y, and Z are parallel, but A and B are not parallel. In addition, putting gold literally within reach of everyone suggests an action for an object i.e. Z: volcanic activity of the compound preposition because of. This is unacceptable.
C is wrong for the same reason as B is wrong.

Between D and E, we expect since to introduce a complete subordinate clause, meanwhile the only verb in the option is taken up by the that modifier. We can eliminate D based on this.
E is correct. Since rightly introduces a complete subordinate clause. The subject of the subordinate clause in E is erosion, prehistoric glacier movement, and ancient, gold-bearing riverbeds. The verb is put. So, we have a complete subordinate clause.

Prospecting for gold during the California gold rush was a relatively easy task, because of erosion, prehistoric glacier movement, and ancient, gold-bearing riverbeds thrust to the surface by volcanic activity put gold literally within reach for anybody with a pan or shovel.

A. because of erosion, prehistoric glacier movement, and ancient, gold-bearing riverbeds thrust to the surface by volcanic activity put gold literally within reach for

B. because of erosion, prehistoric glacier movement, and volcanic activity that thrust ancient, gold-bearing riverbeds to the surface, and putting gold literally within reach of

C. owing to erosion, prehistoric glacier movement, and volcanic activity that had thrust ancient, gold-bearing riverbeds to the surface, and putting gold literally within reach of

D. since erosion, prehistoric glacier movement, and volcanic activity that thrust ancient, gold-bearing riverbeds to the surface, putting gold literally within reach for

E. since erosion, prehistoric glacier movement, and ancient, gold-bearing riverbeds thrust to the surface by volcanic activity put gold literally within reach of

Why the use of "since" is correct in E? "Since" is used to refer to time.

Hello, lakshya14. Although since can refer to time, it can also be used as a conjunction to mean because. Such usage is both grammatically sound and commonplace. Consider, for example,

She was growing increasingly nervous, since the spider was getting closer and closer with each eight-legged step.

Since is often used in place of the more antiquated for in such a construct. There was not a moment in time in which the spider was getting closer, but the reader understands that the latter part of the sentence provides the reason or explanation for why the person was getting nervous. You can check out the eighth definition (no pun intended) of since at dictionary.com, here.

Happy reading.

- Andrew

Prospecting for gold during the California gold rush was a relatively easy task, because of erosion, prehistoric glacier movement, and ancient, gold-bearing riverbeds thrust to the surface by volcanic activity put gold literally within reach for anybody with a pan or shovel.

(B) because of erosion, prehistoric glacier movement, and volcanic activity that thrust ancient, gold-bearing riverbeds to the surface, and putting gold literally within reach of
(C) owing to erosion, prehistoric glacier movement, and volcanic activity that had thrust ancient, gold-bearing riverbeds to the surface, and putting gold literally within reach of
(D) since erosion, prehistoric glacier movement, and volcanic activity that thrust ancient, gold-bearing riverbeds to the surface, putting gold literally within reach for
(E) since erosion, prehistoric glacier movement, and ancient, gold-bearing riverbeds thrust to the surface by volcanic activity put gold literally within reach of

At first, the list seems to be a major distraction here. Which list? Erosion, prehistoric glacier movement, and ancient, gold bearing riverbeds thrust by volcanic activity.. Answer choices (B), (C) and (D) all seem to change the list making it seem that it is better to say erosion, prehistoric glacier movement, and volcanic activity that thrust ancient, gold-bearing riverbeds to the surface. In fact, both versions of the list are fine (as explained by GMATNinja in one of his post above). Then what seems to be the problem?

(A) can be eliminated on the basis of unidiomatic use of 'reach of'. 'reach for' is idiomatically incorrect. Same is the case with (D)
(B) can be eliminated on the basis of use of 'because of' instead of 'because'. The correct version would use, 'because X,Y, and Z put'. Same error as (B) is repeated in (C). Using 'owing to' instead of 'because of' is still incorrect. Additionally (C) can be read as 'Prospecting was a relatively easy task, owing to X, Y, and Z and putting'. Illogical.
(D) incorrectly uses the idiom as observed in (A) as well. Additionally, (D) introduces another error at the end. The statement with option (D) reads as: 'Prospecting was a relatively easy task, since X, Y, and Z, putting'. It seems this choice is trying to convey that the fact that prospecting was a relatively easy task has put gold within reach. We know that X, Y, and Z put the gold within reach.
(E) makes perfect sense. Correcting all error observed in the above options:
'reach of' instead of 'reach for'
'since' instead of 'because of' or 'owing to'
Meaning wise conveying that X,Y, and Z put the gold within reach and thus prospecting was a relatively easy task'