One of the most important tributaries of the Amazon river has fallen

Question

One of the most important  tributaries of the Amazon river has fallen to their lowest - level in over a century, following a fierce drought that as isolated tens of thousands rainforest inhabitants  and raised concerns about the possible impact of climate change on the region.

A. tributaries of the Amazon river has fallen to its lowest level in over a century, following a fierce dought that isolated tens of thousand rainforest inhabitants. 
 
B. tributaries of the Amazon river has fallen to its lowest level in over a century, following a fierce drought that has isolated tens of thousands of rainforest inhabitants 
 
C. tributary of Amazon river has follows to its level in over a century, following a fierce drought that has isolated tens of thousands of rainforest inhabitants 
 
D. tributaries of Amazon river has fallen to its lowest level in over a century, following a fierce drought that has isolated tens of thousand rainforest inhabitants 
 
E. tributaries of the Amazon river has fallen to their lowest levels in over a century, following a fire drought that has isolated tens of thousands of rainforests, in habitants

Mona2019 · Answer

One of the most important  tributaries 
fallen to  its  lowest level
following a fierce drought  that has isolated  and raised concerns

IMO , option D is the answer.

ravigupta2912 · Answer

went with A due to parallelism issue "isolated and raised".

shivasagar94 · Answer

Is the parallelism right in B? Cause 'raised' and 'isolated' seem parallel rather than 'has isolated' and 'raised'. Please explain. Thanks

vv65 · Answer

'Has' is common for both raised and isolated
In 'has isolated and has raised', the second 'has' can be dropped

Posted from my mobile device

jrk23 · Answer

their is wrong in option A. thats why A is wrong(one of the reason).

gvij2017 · Answer

Checkpoint 1.

One of the tributaries has fallen its.... is correct. 
Therefore, C & E are out.

Checkpoint 2. 
Usually option A is same as given in underlined part but "A" statement is differing here.
The problem is with tense structure in "following a fierce drought that isolated". Here we require present perfect tense. 
Option A is out.

Checkpoint 3,

Now between B and D, following a logic that "  Always use articles before: Names of rivers, seas, oceans such as, the Atlantic Ocean, the Black Sea and the Missouri River. Deserts, gulfs, forests or peninsulas such as the Amazon, the Sahara Desert and the Gulf of Mexico. " B is correct. 
B uses The Amazon"

The only difference between

wishalsp333 · Answer

One of the most important tributaries of the Amazon river has fallen to their lowest - level in over a century, following a fierce drought that as isolated tens of thousands rainforest inhabitants and raised concerns about the possible impact of climate change on the region.

A. tributaries of the Amazon river has fallen to its lowest level in over a century, following a fierce dought that isolated tens of thousand rainforest inhabitants.

B. tributaries of the Amazon river has fallen to its lowest level in over a century, following a fierce drought that has isolated tens of thousands of rainforest inhabitants

C. tributary of Amazon river has follows to its level in over a century, following a fierce drought that has isolated tens of thousands of rainforest inhabitants

D. tributaries of Amazon river has fallen to its lowest level in over a century, following a fierce drought that has isolated tens of thousand rainforest inhabitants

E. tributaries of the Amazon river has fallen to their lowest levels in over a century, following a fire drought that has isolated tens of thousands of rainforests, in habitants

Answer choice analysis:

1. Subject-verb agreement : "one of the tributaries" subject and verb "has fallen". No problem here.
2. Verb tense : usage of "has fallen", present perfect it is correct. Because present perfect can be used when an event has occured in past but its effect still continue now.
3. Pronoun : No pronouns here.
4. Modifier : "following" verb-ing modifier is modifying the preceding clause it is correct but there is some error in the modifier. usage of "that as" in modifier is incorrect because in "that" clause there is a verb missing and "as" cannot function as verb here.
5. Parallelism : "isolated" and "raised" are parallel. No issues here.
6. Comparison : No comparison here.
7. Idioms : No idioms here.

A : is rejected as per the reason stated above.
B : corrects all the errors in the sentence. It is the correct answer.
C : Usage of tributary is incorrect here, because it wrong to say "one of the tributary" and "has follows" is incorrect here.
D : "tens of thousand " is incorrect here
E : "in habitants" is placed incorrectly here. By separating like this it changes the meaning of the sentence.

CrackverbalGMAT · Answer

There is a problem with this question. Option (A) does not exactly match with the underlined portion of the original sentence (the question). Hence, I am assuming option (A) to be the correct form and ignoring the underlined portion in the original sentence. There are a few other illogical structures as well which appear to be typos.

One of the most important  tributaries of the Amazon river has fallen to their lowest - level in over a century, following a fierce drought that as isolated tens of thousands rainforest inhabitants  and raised concerns about the possible impact of climate change on the region.

A. tributaries of the Amazon river has fallen to its lowest level in over a century, following a fierce drought that isolated tens of thousand rainforest inhabitants  The sentence is in the present perfect tense (" has  fallen"). Therefore, we must have a "has" before isolated since the isolation happened in the past and continues to the present (as evidenced by the earlier usage of "has fallen"). Eliminate.

B. tributaries of the Amazon river has fallen to its lowest level in over a century, following a fierce drought that has isolated tens of thousands of rainforest inhabitants  Correct answer. Uses present perfect tense throughout and no other errors are introduced.

C. tributary of Amazon river has follows to its level in over a century, following a fierce drought that has isolated tens of thousands of rainforest inhabitants  "has follows" seems to be a typo. Ignoring that, "tributary" in singular form is an error as we are talking about one of of many tributaries. Plural form is needed. Eliminate.

D. tributaries of Amazon river has fallen to its lowest level in over a century, following a fierce drought that has isolated tens of thousand rainforest inhabitants  We need an article before the name of the river Amazon. Eliminate.

E. tributaries of the Amazon river has fallen to their lowest levels in over a century, following a fire drought that has isolated tens of thousands of rainforests, in habitants  Only one of the tributaries has fallen to its lowest level. Hence, pronoun used should be singular form "its" and not plural form "their". "In habitants" appears to be a typo. There could be an apostrophe missing in "rainforests". These issues are not clear. Eliminate.

Hope this helps.

CrackverbalGMAT · Answer

Hi Shiva

When assessing parallelism, it helps to think about the sentence as being structured as a mathematical expression with parentheses, with the items of the list appearing inside. As in math, the portion outside the parentheses will be applicable to each of the terms inside the parentheses (here, the items of the list). For example:

At the next meeting, the company directors will  ( assess the yearly plan, discuss the compensation policy, and make a final decision regarding closure of the Bosnian operations ) .

Here, the parentheses opens after "will". So "the directors will" is applicable to each of "assess...", "discuss..." and "make...", and is correct. We could also have the parentheses open after "directors", in which case the sentence will read as follows, and is also correct.

At the next meeting, the company directors  ( will assess the yearly plan, will discuss the compensation policy, and will make a final decision regarding closure of the Bosnian operations ) .

By this logic, in the above sentence, the parentheses will be as below:

One of the most important  tributaries of the Amazon river has fallen to its lowest level in over a century, following a fierce drought that has  ( isolated tens of thousands of rainforest inhabitants  and raised concerns about the possible impact of climate change on the region ) .

Thus, "has" will be applicable to both "isolated" and "raised". There is nothing wrong with this form. Hope this clarifies.

One of the most important tributaries of the Amazon river has fallen

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One of the most important tributaries of the Amazon river has fallen

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