Experts please help!

[GmatKiss]

Geologists believe that the warning signs for a major earthquake may include sudden fluctuations in local seismic activity, tilting and other deformations of the Earth's crust, changing the measured stain across a fault zone, and varying the electrical properties of underground rocks.

(A) changing the measured strain across a fault zone, and varying
(B) changing measurements of the strain across a fault zone, and varying
(C) changing the strain as measured across a fault zone, and variations of
(D) changes in the measured strain across a fault zone, and variations in
(E) changes in measurements of the strain across a fault zone, and variations among

OA after some discussion

[patanjali.purpose]

Geologists believe that the warning signs for a major earthquake may include sudden fluctuations in local seismic activity, tilting and other deformations of the Earth's crust, changing the measured stain across a fault zone, and varying the electrical properties of underground rocks.

(A) changing the measured strain across a fault zone, and varying
(B) changing measurements of the strain across a fault zone, and varying
(C) changing the strain as measured across a fault zone, and variations of
(D) changes in the measured strain across a fault zone, and variations in
(E) changes in measurements of the strain across a fault zone, and variations among

OA after some discussion

sudden fluctuations in local seismic activity, tilting and other deformations of the Earth's crust ==> parallel elements 'adjective/noun/prepositional phrase' eg sudden (adj) fluctuations (noun) in local seismic activity (prep ph). [spoiler]Only B follows this trend IMO: B[/spoiler]

[sunny.bhasin]

the answer seems to be option b to me as for the sentence to be parallel we need to eliminate d and e.
a and c changes the meaning so answer is b.

[akhilsuhag]

I would go with D.
Somehow sounds more parallel to me.

Waiting for the OA

[arashyazdiha]

I would go with D.
The question is asking for parallel structure and it is the matter of comma.If the 'and' between tilting and other deformations of the Earth's crust were to act as a conjunction between itself and earth sudden fluctuations in local seismic activity and other deformations, then there would be also a comma after tilting. But it is important that in does not stop here and the comma comes after in the deformation of the earth's crust: so I think these things must be in parallel:
sudden fluctuations in local seismic activity
tilting and other deformations of the earth's crust
changes in the measures strain across a fault zone
variations in the electrical properties of underground rocks

Bests
Arash

[top_business_2011]

Geologists believe that the warning signs for a major earthquake may include sudden fluctuations in local seismic activity, tilting and other deformations of the Earth's crust, changing the measured stain across a fault zone, and varying the electrical properties of underground rocks.

(A) changing the measured strain across a fault zone, and varying
(B) changing measurements of the strain across a fault zone, and varying
(C) changing the strain as measured across a fault zone, and variations of
(D) changes in the measured strain across a fault zone, and variations in
(E) changes in measurements of the strain across a fault zone, and variations among

OA after some discussion

The answer is D.

Let's see:
...sudden fluctuations in local seismic activity, tilting and other deformations of the Earth's crust....

See that? each phrase starts with a noun; so for the sake of parallelism, the remaining phrases should also start with nouns.

(A) changing the measured strain across a fault zone, and varying [Start with -ing verbs, so incorrect]
(B) changing measurements of the strain across a fault zone, and varying[ Though the first is a noun, such presentation distorts the meaning. The second is not a noun]
(C) changing the strain as measured across a fault zone, and variations of [Similar Problem]
D) changes in the measured strain across a fault zone, and variations in [ Both 'changes' and 'variations' are nouns; Hence, D is the best answer]
(E) changes in measurements of the strain across a fault zone, and variations among[ It distorts the intended meaning]

[GmatKiss]

OA is indeed D

[Target2009]

+1 to D

[prateek_guy2004]

IMO A, That's look parallel to me....

[e-GMAT]

This is another one of those questions that should be approached logically. Please review detailed solution of this question at this link - https://e-gmat.com/blogs/?p=549.

I will paste the meaning analysis part here.

This sentence provides 4 warning signs for a major earthquake. These are:

1. Sudden fluctuations in local seismic activity
2. Titling and other deformations of crust
3. Changes in measured strain
4. Variation in electrical properties of rocks

A key thing to note in this sentence is that the intended meaning conveyed may be little difficult to comprehend because of the construction of elements 3 and 4. Elements 1 and 2 are clearly nouns (note that tilting is a noun here). Elements 3 and 4 are written in verb-ing form, making it appear as though these two are presenting results of the previous clause. Warning signs may include A and B, changing the strain, and varying the electrical properties...This cannot be the correct interpretation for the following reasons:

1: The meaning itself is non-sensical. It does not make sense to say that warning signs includes A and B, and this causes change in measured strain and variation in electrical properties.
2: Grammatically as well, this is incorrect. In the non-underlined portion of the sentence, "may include A and B" is written as "may include A, B" - If a list contains 2 elements, it should be connected properly using "and" in this case.

For further analysis, you may refer to the link above.

Hope this helps.

Payal

[prateek_guy2004]

ya i get know D should be the answer......

[patanjali.purpose]

This is another one of those questions that should be approached logically. Please review detailed solution of this question at this link - https://e-gmat.com/blogs/?p=549.

I will paste the meaning analysis part here.

This sentence provides 4 warning signs for a major earthquake. These are:

1. Sudden fluctuations in local seismic activity
2. Titling and other deformations of crust
3. Changes in measured strain
4. Variation in electrical properties of rocks

A key thing to note in this sentence is that the intended meaning conveyed may be little difficult to comprehend because of the construction of elements 3 and 4. Elements 1 and 2 are clearly nouns (note that tilting is a noun here). Elements 3 and 4 are written in verb-ing form, making it appear as though these two are presenting results of the previous clause. Warning signs may include A and B, changing the strain, and varying the electrical properties...This cannot be the correct interpretation for the following reasons:

1: The meaning itself is non-sensical. It does not make sense to say that warning signs includes A and B, and this causes change in measured strain and variation in electrical properties.
2: Grammatically as well, this is incorrect. In the non-underlined portion of the sentence, "may include A and B" is written as "may include A, B" - If a list contains 2 elements, it should be connected properly using "and" in this case.

For further analysis, you may refer to the link above.

Hope this helps.

Payal

Thanks Payal.

Great explanation.

I ignored D & E thinking that changes & variations are verb. I was sure that I require NOUN to make element 3 & 4 parallel to 1 & 2 but mistook changes/variations for verbs. After reading your explnation realized that 'sentence already has verb 'may include' so how can 'changes/variations act as verb here.

Could you also explain how can I avoid interpreting 'variations/changes' as verb in future question. Is this related to recognizing verbs? Thanks for help.

[hasija]

Geologists believe that the warning signs for a major earthquake may include sudden fluctuations in local seismic activity, tilting and other deformations of the Earth's crust, changing the measured stain across a fault zone, and varying the electrical properties of underground rocks.

(A) changing the measured strain across a fault zone, and varying
(B) changing measurements of the strain across a fault zone, and varying
(C) changing the strain as measured across a fault zone, and variations of
(D) changes in the measured strain across a fault zone, and variations in
(E) changes in measurements of the strain across a fault zone, and variations among

OA after some discussion

Lets see it other way out...fluctuations in, changes in and variations in is the best parallelism , I can point here. Therefore D is clearly the ans.

[e-GMAT]

Thanks Payal.

Great explanation.

I ignored D & E thinking that changes & variations are verb. I was sure that I require NOUN to make element 3 & 4 parallel to 1 & 2 but mistook changes/variations for verbs. After reading your explnation realized that 'sentence already has verb 'may include' so how can 'changes/variations act as verb here.

Could you also explain how can I avoid interpreting 'variations/changes' as verb in future question. Is this related to recognizing verbs? Thanks for help.

Hi Patanjali,

Verbing words can be confusing. This is because these words are multi- faceted. Here are the roles that a verb-ing word can play.

1: Verb
2: Adjective
3: Noun

1: Mary is singing. - Verb
2A: The little bird, singing along the way, sat on the branch to drink some water from the bird feeder. - Adjective (Modifier)
2B: The falling property values are causing discomfort in the market. - Adjective
3: Singing is Mary's passion. - Noun

You asked specifically how not to confuse a verbing word to be a verb. The test for that is relatively simple. A verbing word is a verb only if it is preceded by is/are/was/were/am. Notice how "singing" is preceded by "is" in sentence 1 in which "singing" is a verb.

Please note that this rule is covered in detail in the concept - SV-Must Exist in e-GMAT. This is also available in the free trial of the SC course.

Hope this helps.

Regards,

Payal