Manipulating ecosystems to wipe out disease-carrying mosquitoes seems

OFFICIAL EXPLANATION



THE PROMPT


• Meaning?
Manipulating ecosystems to wipe out disease-carrying mosquitoes
(1) seems to be a good way to eradicate malaria quickly, and
(2) [is] an idea whose benefits outweigh its environmental costs

• Structure of this sentence?
Let's look at the part at the end and correct a pronoun error: "an idea whose benefits outweigh its environmental costs."

→ That whole thing is called a summative modifier.
The writer makes up a word (usually a noun phrase) that "summarizes" or encapsulates the idea expressed in the previous clause (hence "summative").
This noun phrase describes the noun-thing that happened in the previous clause and gives more detail about that clause.
A summative modifier is a special kind of appositive.

→ Why am I talking about this issue even though it is not a decision point?
GMAC likes to test these summative modifiers.
They are integral to sophisticated prose.
If you see a strange-looking modifier (or bunch of words that appear to be "tacked on" to the sentence), check to see whether that modifier or that bunch of words uses a noun phrase to capture the idea expressed in the previous clause.
→ in this case, "an idea" refers to the fact that manipulating ecosystems to wipe out disease-carrying mosquitoes seems to be a good way to eliminate malaria quickly.

THE OPTIONS


• noun/pronoun disagreement
→ what thing has benefits and costs? An idea.
→ an idea is singular. Its benefits outweigh ITS costs. (Not their.)
That is, the plural their cannot refer back to the singular idea
ELIMINATE A


• subject-verb agreement
→ The singular subject manipulating ecosystems requires the singular verb seems (not seem).
ELIMINATE B


• that creates a nonsensical sentence
→ With the full sentence, we have
Manipulating ecosystems that wipe out disease-carrying mosquitoes

→ The ecosystems themselves do not wipe out the mosquitoes.

• what does whose refer to?
I suppose we could argue that the only logical candidate is manipulating ecosystems.
That whose is a long way from the noun it allegedly describes; noun modifiers should be as close as possible to their nouns.
The meaning problem, above, is fatal. This one is harder to analyze. Pick one error and move on.
ELIMINATE C


• subject-verb agreement
→ The singular subject manipulating ecosystems requires the singular verb seems (not seem).

• noun/pronoun disagreement
The benefits of the idea outweigh the costs of the idea, requiring the singular its to refer to the singular idea.
ELIMINATE D


• I do not see any errors
• the singular verb seems is correctly paired with its singular subject, "manipulating ecosystems to wipe out disease-carrying mosquitoes."
(Gerund clauses -- verbING clauses in which the verbING acts as a noun -- are always singular.)
• the pronoun usage is correct.
→ the idea's benefits (its benefits) outweigh the idea's (its ideas) environmental costs.

The answer is E.

COMMENTS

We have a nice collection of veterans and newcomers, all of whom wrote answers with good analysis.

Keep up the good work.
Kudos to all.

My answer is (E). It took me 01:21.

(A) "their environmental costs" should be "its environmental costs"; "its" refers tp "an idea".

(B) "seem" should be "seems" because the subject "Manipulating ecosystems to wipe out disease-carrying mosquitoes" is singular.

(C) (1) "whose benefits" = "malaria's benefits" is nonsensical. (2) "that wipe out" modifies "ecosystems", but we do not have such ecosystems to manipulate.

(D) Not a sentence. There are two verbs: seem like & "is".
Also, see (A) and (B).

Manipulating ecosystems to wipe out disease-carrying mosquitoes seems like a good way for eradicating malaria overnight, an idea whose benefits outweigh their environmental costs.

A) to wipe out disease-carrying mosquitoes seems like a good way to eradicate malaria overnight, an idea whose benefits outweigh their Incorrect

B) to wipe out disease-carrying mosquitoes seem to be a good way to eradicate malaria overnight, an idea whose benefits outweigh its Incorrect

C) that wipe out disease-carrying mosquitoes seems to be a good way to eradicate malaria overnight, whose benefits outweigh its Incorrect

D) to wipe out disease-carrying mosquitoes seem like a good way of eradicating malaria overnight is an idea whose benefits outweigh their Incorrect

E) to wipe out disease-carrying mosquitoes seems to be a good way to eradicate malaria overnight, an idea whose benefits outweigh its Correct


POE -

Manipulating singular, so seem should be seems; seems like incorrect idioms
Eliminate A, B & D
C has modifier problem, an idea is better uses than whose
Answer E
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Manipulating ecosystems to wipe out disease-carrying mosquitoes seems like a good way for eradicating malaria overnight, an idea whose benefits outweigh their environmental costs.
Sentence Structure
Manipulating ecosystems (doing something - here "Manipulating" is acting as noun and subject of the sentence)
----- to wipe out disease-carrying mosquitoes
-seems like a good way for eradicating malaria overnight,
-----an idea whose benefits outweigh their environmental costs. (this is NOUN + Noun modifier - appears to be modifying the complete preceding clause)

Error:
1. Meaning of the sentence seems fine
2. In the Noun + noun modifier section - "their" referring to idea and not ideas - so sentence has pronoun antecedent error

POE

A) to wipe out disease-carrying mosquitoes seems like a good way to eradicate malaria overnight, an idea whose benefits outweigh their - Pronoun antecedent error

B) to wipe out disease-carrying mosquitoes seem to be a good way to eradicate malaria overnight, an idea whose benefits outweigh its - SV error

C) that wipe out disease-carrying mosquitoes seems to be a good way to eradicate malaria overnight, whose benefits outweigh its
- as per original sentence action of manipulation is done with an intention to achieve something but this option is distorting the meaning
- Pronoun ambiguity - whose does not have clear antecedent, whose can not modify the whole clause

D) to wipe out disease-carrying mosquitoes seem like a good way of eradicating malaria overnight is an idea whose benefits outweigh their
- SV Error
- Structural error - S + V + V - not connected properly - not making sense
- Pronoun antecedent Error

E) to wipe out disease-carrying mosquitoes seems to be a good way to eradicate malaria overnight, an idea whose benefits outweigh its
- SV pair seems fine
- their - changed to its
- Clear meaning
- CORRECT

Manipulating ecosystems to wipe out disease-carrying mosquitoes seems like a good way for eradicating malaria overnight, an idea whose benefits outweigh their environmental costs.

A) to wipe out disease-carrying mosquitoes seems like a good way to eradicate malaria overnight, an idea whose benefits outweigh their

generis Option A needs to be edited - see -"to eradicate/for eradicating"

To eradicate, however, indicates the purpose and its correct.

B) to wipe out disease-carrying mosquitoes seem to be a good way to eradicate malaria overnight, an idea whose benefits outweigh its

S-V agreement error
Subject is "Ving phrase = Manipulating ecosystems"

C) that wipe out disease-carrying mosquitoes seems to be a good way to eradicate malaria overnight, whose benefits outweigh its

Meaning changed

Manipulating ecosystems that wipe out - Eliminate + Structural issue in sentence

D) to wipe out disease-carrying mosquitoes seem like a good way of eradicating malaria overnight is an idea whose benefits outweigh their

Structural issue - Not a legit sentence
Pronoun error- Their has no logical reference

E) to wipe out disease-carrying mosquitoes seems to be a good way to eradicate malaria overnight, an idea whose benefits outweigh its

(E) is the Correct answer

ERROR ANALYSIS -

1) 'seems like' - this is redundant
2) 'their' doesn't agree in number

ANSWER CHOICE ANALYSIS -

A) 'their' doesn't agree in number
B) 'seem' - doesn't agree in number - refers to the idea
C) 'whose' - relative pronoun must refer to the noun preceding
D) 'their' doesn't agree in number
E) CORRECT

sumitkrocks , edited. Thank you.
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The official explanation is here.
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