Pack 19 Q1: The symbiotic relationship of some animal species...

Question

Pack 19, Question 1 of 5:

The symbiotic relationship of some animal species, including the bacterium  Buchnera aphidicola  and  aphids have existed for so long, though inseparable  from one another.

A. aphids have existed for so long, though inseparable
B. aphids has existed for so long but are not inseparable
C. aphids, has existed for so long that they are inseparable
D. aphids—has existed for so long but they are not separable
E. also aphids, for so long has existed not inseparable

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HoneyLemon · Answer

imo  C

A. aphids  have  existed for so long, though inseparable

-- relationship is singular

B. aphids  ,  has existed for so long but are not inseparable

--lack of comma - made the sentence no verb 
 
C. aphids, has existed for so long that they are inseparable
 -- Correct

D. aphids — has existed for so long  but  they are not separable
 -- Sentence structure error and meaning is also distorted with the presence of word but.

E. also aphids,  for so long  has existed  not inseparable 
 and also is redundant . Seems illogical with not inseparable

winterschool · Answer

The symbiotic relationship of some animal species, including the bacterium Buchnera aphidicola and aphids have existed for so long, though inseparable from one another.

A. aphids  have  existed for so long,  though inseparable   Incorrect

original sentence is awkward, some part of original sentences included with modifier
 
B. aphids has existed for  so  long  but  are not inseparable  Incorrect

...so ...that .....correct idioms; original sentence is incomplete

C.  aphids, has existed for so long that they are inseparable   Correct

D. aphids—has existed for  so  long  but  they are not separable  Incorrect

...so ...that .....correct idioms

E. also aphids,  for so long has existed not inseparable   Incorrect

awkward construction

prateekchugh · Answer

The symbiotic relationship of some animal species, including the bacterium Buchnera aphidicola and   aphids have existed for so long, though inseparable   from one another.

A. aphids  have  existed for so long, though inseparable    The symbiotic relationship is Singular subject; require singular verb Incorrect  
B. aphids has existed for  so  long  but  are not inseparable   The symbiotic relationship.....has existed but The symbiotic relationship are not inseparable. 
1) Subject-Verb agreement error, it should be singular verb
2) Subject-Verb meaning error in The symbiotic relationship are not inseparable. Its relationship or animal species
3) So X that Y....Correct...So x BUT y....Incorrect

C. aphids, has existed for so long that they are inseparable   Correct Answer  
D. aphids — has existed for so long but they are not separable   The symbiotic relationship....., including.....aphids-.....In place of '-' it should be a comma. Incorrect Choice

E.  also  aphids, for so long has existed not inseparable   The symbiotic relationship......and also..... Redundancy error

Sushil117 · Answer

A. aphids have existed for so long, though inseparable
"have", SVA error

B. aphids has existed for so long but are not inseparable
Incorrect

C. aphids, has existed for so long that they are inseparable
Correct

D. aphids—has existed for so long but they are not separable
Use of "but" seems incorrect

E. also aphids, for so long has existed not inseparable
Changes meaning

Posted from my mobile device

Varunsawhney8 · Answer

The symbiotic relationship of some animal species, including the bacterium Buchnera aphidicola and aphids have existed for so long, though inseparable from one another.

First what is verb has/have is referring to - The symbiotic relationship
So The symbiotic relationship is singular use of Singular Verb is correct

A. aphids have existed for so long, though inseparable
In this sentence No Main Verb is present
also have is now referring to bacterium relationship
Incorrect

B. aphids has existed for so long but are not inseparable
In this sentence No Main Verb is present
also has is now referring to bacterium relationship
Incorrect

C. aphids, has existed for so long that they are inseparable
Idiom Correct -> So X that.. Noun
has- The Symbolic relationship
Correct Choice

D. aphids—has existed for so long but they are not separable
Idiom Incorrect -> Correct Idiom is So X that.. Noun
has- The Symbolic relationship
Incorrect Choice

E. also aphids, for so long has existed not inseparable
also is redundant
For is not required and is making the part another dependable clause thereby no main verb
Idiom error
So Long is not correct

Incorrect

nothing345 · Answer

The symbiotic relationship of some animal species, including the bacterium Buchnera aphidicola and aphids have existed for so long, though inseparable from one another.

A. aphids  have  existed for so long, though inseparable
 Relationship is singular not plural. Subject Verb Agreement Error.

B.  aphids has  existed for so long but are not inseparable
 Need a comma after aphids otherwise the meaning changes.

C. aphids, has existed for so long that they are inseparable
 Fixes all other errors.

D. aphids —has  existed for so long  but  they are not separable
 There should be a comma instead of a dash. But changes the meaning.

E.  also aphids,  for so long has existed  not inseparable 
 Distorted meaning and not inseparable wordy

NiftyNiffler · Answer

The symbiotic relationship of some animal species, including the bacterium Buchnera aphidicola and  aphids have existed for so long, though inseparable  from one another.

A. aphids  have  existed for so long, though inseparable -- singular subject is "symbiotic relationship", so verb "have existed" leads to SVA error
B. aphids has existed for so long but  are  not inseparable -- though error in A is eliminated, a new plural verb error is introduced after conjunction "but"
C. aphids,  has  existed for so long that  they  are inseparable -- CORRECT, "they" here refers to species which is plural
D. aphids —has  existed for so long  but  they are not separable -- m-dash can't be used in front of main verb. That leads to sentence fragment
E. also aphids,  for so long has existed not inseparable  -- nonsensical and grammatically incorrect

The answer should be  C , IMO

EMPOWERgmatVerbal · Answer

Official Explanation

The symbiotic relationship of some animal species, including the bacterium Buchnera aphidicola and  aphids have existed for so long, though inseparable  from one another.
 
 A. aphids  have existed  for so long , though inseparable  
 B. aphids  has existed  for so long  but are not inseparable  
 C. aphids,  has existed  for so long  that they are inseparable  
 D. aphids— has existed  for so long  but they are not separable  
 E. also aphids, for so long  has existed   not inseparable

After a quick glance, it’s clear that there are several differences we can focus on here, but let’s narrow it down to just a couple differences to start:

1. have existed vs. has existed (Verb Tense)
2. though inseparable / but are not inseparable / that they are inseparable / but they are not separable / not inseparable (Structure & Meaning) 
 
 While it might be tempting to start with #1 because it’s an either/or split, look closely – it’s a 4-to-1 split.  Odds are, you won’t eliminate 4 options based on something as simple as a verb choice. Instead, let’s tackle #2, which has to do with structure.

If we look closely at the original sentence, it appears to use a non-essential clause to give an example of a symbiotic relationship (a type of bacteria and aphids). We need to make sure this non-essential clause can be removed without creating a sentence fragment or run-on. To make problems easier to spot, let’s add in the non-underlined portions.

A.  The symbiotic relationship of some animal species , including the bacterium Buchnera aphidicola and  aphids  have existed  for so long,   though inseparable   from one another. 
This is  INCORRECT  because, if we remove the non-essential clause that’s bookended with commas, we’re left with a sentence fragment. This means that the verb (have existed) was accidentally included in the non-essential clause! Also, the plural verb “have existed” doesn’t match the singular subject “relationship.”

B. The symbiotic relationship of some animal species , including the bacterium Buchnera aphidicola and    aphids has existed  for so long but are not inseparable  from one another.
This is  INCORRECT  because the writer forgot the put the comma after “aphids,” which would have closed off the non-essential clause. Now we’re left with a subject and one very long -ing modifier that is worded awkwardly and also swallowed up our verb!

C.  The symbiotic relationship of some animal species , including the bacterium Buchnera aphidicola and  aphids,  has existed for so long that they are inseparable    from one another. 
Here is our  CORRECT  choice! If we remove the non-essential clause (including the bacterium Buchnera aphidicola and aphids), what we’re left with is still a complete sentence.

D. The symbiotic relationship of some animal species , including  the bacterium Buchnera aphidicola and   aphids—has  existed for so long but they are not separable  from one another.
This is  INCORRECT  because, whenever we add in a non-essential clause, the punctuation before and after need to match. You could use commas or hyphens – but you cannot use both.

E. The symbiotic relationship of some animal species, including the bacterium Buchnera aphidicola  and    also  aphids, for so long has existed   not inseparable   from one another .
This is  INCORRECT  for a couple reasons. First, saying “and also” is not necessary – it’s overly wordy. Second, even if we take out the non-essential clause, we have a meaning problem. By using the double-negative “not inseparable,” the meaning is fundamentally changed. This is saying that symbiotic species are actually separate from each other, which is NOT the meaning we’re trying to convey! Option C clearly shows that species that are in a symbiotic relationship are inseparable, which makes much more sense.
 
 There you have it – option C is our winner!

Don’t study for the GMAT. Train for it.

EMPOWERgmatVerbal · Answer

Well done HoneyLemon ! You cracked the code on this one - kudos to you!

EMPOWERgmatVerbal · Answer

Well done winterschool ! Great catch with the idiom problem! Kudos to you!

EMPOWERgmatVerbal · Answer

Well done prateekchugh ! You cracked the code on this one! Kudos to you!

EMPOWERgmatVerbal · Answer

Well done, SKY396 ! Make sure to explain what is right/wrong with each option - we see that you ruled out option B, but we're eager to know why! Kudos to you, and we look forward to more explanations from you in the rest of the pack!

EMPOWERgmatVerbal · Answer

Great explanation Varunsawhney8 ! Kudos to you!

EMPOWERgmatVerbal · Answer

Another great explanation, nothing345 ! Kudos to you! We look forward to getting your input on the rest of this pack of questions!

EMPOWERgmatVerbal · Answer

Another great explanation NiftyNiffler ! Looking forward to seeing how you tackle the rest in this pack! Kudos to you!

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Pack 19 Q1: The symbiotic relationship of some animal species...

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Pack 19 Q1: The symbiotic relationship of some animal species...

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615 to 715 in 15 Days (Ria's Strategies)

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