Caterpillars of all species produce an identical hormone called "juven

Question

Caterpillars of all species produce an identical hormone called "juvenile hormone" that maintains feeding behavior. Only when a caterpillar has grown to the right size for pupation to take place does a special enzyme halt the production of juvenile hormone. This enzyme can be synthesized and will, on being ingested by immature caterpillars, kill them by stopping them from feeding.

Which of the following, if true, most strongly supports the view that it would  not  be advisable to try to eradicate agricultural pests that go through a caterpillar stage by spraying croplands with the enzyme mentioned above?

(A) Most species of caterpillar are subject to some natural predation.

(B) Many agricultural pests do not go through a caterpillar stage.

(C) Many agriculturally beneficial insects go through a caterpillar stage.

(D) Since caterpillars of different species emerge at different times, several sprayings would be necessary.

(E) Although the enzyme has been synthesized in the laboratory, no large-scale production facilities exist as yet.

ID: 100949

ChiranjeevSingh · Accepted Answer

Understanding the Passage

Caterpillars of all species produce an identical hormone called “juvenile hormone” that maintains feeding behavior.

All caterpillars produce the same “juvenile hormone” (I wonder why it is called juvenile – which means immature or young!). This hormone maintains the eating behavior of the caterpillars.

Only when a caterpillar has grown to the right size for pupation to take place

I don’t know what pupation is. Perhaps, it’s a stage of development for caterpillars. I understand that there is a ‘right size’ for pupation to happen. The statement says that only when a caterpillar reaches this stage. Then what?

does a special enzyme halt the production of juvenile hormone.

Only then a special enzyme halts the production of juvenile hormone. So, before a caterpillar reaches this stage (grown to the right size for pupation to happen), this special enzyme doesn’t halt the production of juvenile hormone. (Given that juvenile hormone maintains eating behavior, I wonder what would happen once its production is halted! How would a caterpillar maintain its feeding behavior?)

This enzyme can be synthesized and will, on being ingested by immature caterpillars, kill them by stopping them from feeding.

This enzyme can be produced artificially and will kill the caterpillar if it is ingested by immature caterpillars. How will it kill them? By stopping them from feeding. (This makes sense since we’re already given that juvenile hormone maintains feeding behavior and that the production of juvenile hormone is halted by the enzyme. Thus, if this enzyme is ingested, the production of the juvenile hormone will stop, and the feeding behavior will not be maintained.)

Understanding the Question Stem

Which of the following, if true, –

“If true” means that we’re supposed to take the option statements at face value; we’re not supposed to question their validity or truth value.

most strongly supports the view-

We’re looking for an option that most strongly supports a particular view. Since it says “most strongly supports”, we can have multiple options supporting the view, but we’re looking for an option that supports the view most strongly.*

that it would not be advisable to try to eradicate agricultural pests that go through a caterpillar stage by spraying croplands with the enzyme mentioned above?

The view is that it would NOT be advisable to kill agricultural pests that go through a caterpillar stage by spraying the enzyme mentioned above on the croplands.
(The passage said that the enzyme can be produced artificially and will kill immature caterpillars on being ingested, but the view is that it would not be advisable to do so.)

- - -

We’re looking for an option that most strongly GOES AGAINST spraying the enzyme on the cropland to kill the agricultural pests that go through a caterpillar stage.

Predicting Possible Answers -

We’re looking for a disadvantage of spraying the enzyme on the cropland to kill the agricultural pests that go through a caterpillar stage.

I can think of the following: 
1. Perhaps, spraying this enzyme on the cropland harms the cropland in some way.
2. Perhaps, immature caterpillars of agricultural pests will not ingest anything from outside. We’re given that the enzyme needs to be ingested by an immature caterpillar. What if that doesn’t happen in the case of agricultural pests? (They’re smart!)

The Evaluation

Before I evaluate options, I make sure that I’m very clear about what I’m looking for in the options. Do you also do so?

I’m looking for an option that supports the view. Which view? The view that it would NOT be advisable to kill agricultural pests that go through a caterpillar stage by spraying the enzyme mentioned above on the croplands.

(A) Most species of caterpillar are subject to some natural predation.

Incorrect.   This option has NO IMPACT on the view.

The option says that some caterpillars of most species are killed by natural predators.

Even if some caterpillars are killed this way, why shouldn’t we kill the remaining caterpillars of agricultural pests by spraying the enzyme?

This option doesn’t give any reason for this. Thus, this option has no impact on the view.

(B) Many agricultural pests do not go through a caterpillar stage.

Incorrect.  This option has no impact on the view. Why?

Because the view pertains to killing the agricultural pests  that go through a caterpillar stage . (Did you miss this?!)

Even if many pests do not go through a caterpillar stage, the view is not impacted.

(C) Many agriculturally beneficial insects go through a caterpillar stage.

Correct.    A very important word in this option is “beneficial”.

If there are agriculturally beneficial insects that go through a caterpillar stage, spraying the enzyme on the cropland may harm the cropland by killing these beneficial insects.

Thus, we have a reason to argue against spraying the enzyme on the cropland. Therefore, this option supports the view.

(D) Since caterpillars of different species emerge at different times, several sprayings would be necessary.

Incorrect.   The fact that several sprayings would be necessary to kill the caterpillars of the pests presents a disadvantage. Thus, this option supports the view.

However, compared to option C, this option presents a much less serious disadvantage. While the disadvantage presented in option C doesn’t seem to be possible to overcome, the disadvantage presented in this option is not a significant one. Perhaps, doing the spraying several times is not an issue – it is perhaps very convenient and inexpensive. Or, perhaps, we spray only once and choose to eradicate only some of the pests.

Without being given any serious disadvantage of several sprayings, this option has a very mild effect on the view.

Thus, while this option supports the view, it is nowhere as strong as option C in supporting the view.

(E) Although the enzyme has been synthesized in the laboratory, no large-scale production facilities exist as yet.

Incorrect.   This option has NO IMPACT on the view.

This option suggests that we don’t  currently  have a sufficient amount of enzyme to spray on the cropland. However, not having the enzyme  currently  CANNOT be a reason to argue that we should not use it to kill agricultural pests.

For example, you may not have an iPhone right now. However, this fact cannot be a reason to support that you SHOULD NOT use an iPhone to make calls.

- - -

*In more than 90% of these questions, there is  only one  option that supports; other options have no impact or weaken. However, this particular question falls into the less than 10% category; it has two options that support the view

- - -

By the way, have you heard of the caterpillar and butterfly story? It’s a very beautiful story. You can read it here: The Caterpillar And The Butterfly – International Story

CrackverbalGMAT · Answer

Let's break down the argument: 
Juvenile Hormone - > Kills Caterpillars

Task: The answer should provide a reason that will show that spraying Juvenile hormone is NOT advisable.

The biggest assumption the author of the argument makes is that- Killing caterpillars is Good; or in other words - All caterpillars are bad.

This assumption if proven wrong. Will highlight a reason NOT to go ahead with the suggested plan. 
We need an answer choice, therefore, that brings out some disadvantage that killing caterpillars through this method might bring.

Lets explore the answer choices: 
A. We are not bothered about "natural predators" - this is out of scope : Eliminate
B. If this statement were true. Caterpillars will be killed -> some pests will be killed therefore. This doesn't bring out any negative consequence. Sure many pest will remain unharmed (because they don't go through a caterpillar stage - but the argument isn't bothered about this, and neither must you!) : Eliminate
C. Yes, this says that some beneficial insects go through caterpillar phase and will as a consequence be killed by the "Juvenile Hormone" -> this shows a clear negative consequence to following the proposed plan. This is the correct answer.
D. That several spraying will be necessary is irrelevant and is not really a negative Consequence : Eliminate
E. That large scale production facilities don't exist isn't a negative consequence either : Eliminate

Hope that Helped!

Ajeeth Peo 
Verbal Instructor

banerjeea_98 · Answer

"C"....we r concerned abt getting rid of few pests that go thro the caterpillar stages...."B" is not it, becose even if many of the paets don't go thro the stages, but we can still achieve our goal to eradicate the ones that do go thro those stages, as we r not out to eradicate all pests. Only C has a bad side effect of spraying.

HongHu · Answer

I would choose C too. Almost chosen B, but on a closer look at the question, it says why it is not advisable to use the enzyme to kill agricultural pests  that go through a caterpillar stage .

jlgdr · Answer

Has anyone found the OA for this one? I chose B by POE because it is the answer choice that to me makes more sense. Let's quickly go through the answer choices A: Out of scope B: This may be right, still I'm not too sure because it uses the word many, what about the others? But i'll leave it in for the time being. C: This actually says the opposite of what we want. This would say why it WOULD be advisable D: So what? If different sprayings are necessary then let's do it. Not too big of a deal. Still I'll leave it in just in case E: Out of scope. I don't really care as long as I can get it somehow. And this is not what we are asked So between B and D. Not be advisable huh? I think B is just a little bit better as an answer choice but to me it is a really close call unless I am missing something. Experts please? Any words of wisdom on the passage? Thanks Cheers J

akashb106 · Answer

The OA is C for this question. It is in OG 12th Edition.

A Spraying would eradicate all pests that go through a caterpillar stage and so is more eff ective than
natural predators are. This statement provides no reason not to spray.
B Spraying aff ects only those agricultural pests that do go through a caterpillar stage, so this
statement is irrelevant.
C Correct. Th is statement properly identifi es evidence that strengthens the argument against
spraying.
D The need to spray repeatedly does not provide any significant evidence that spraying is
inadvisable, but simply suggests that the process will be more complicated.
E The mere lack of current production facilities does not mean that it would be inadvisable to
develop and use the spray in the future.
Th e correct answer is C.

ritikasingh · Answer

(C)
The keyword here is 'agriculturally  beneficial  insects'. Since many agriculturally beneficial insects also go through caterpillar stage, spraying this enzyme on the crop might stop them from feeding and eventually kill them. But since they are actually beneficial to the crop, this is  not  desired or advised.

twistedphoton · Answer

Caterpillars of all species produce an identical hormone called "juvenile hormone" that maintains feeding behavior. Only when a caterpillar has grown to the right size for pupation to take place does a special enzyme halt the production of juvenile hormone. This enzyme can be synthesized and will, on being ingested by immature caterpillars, kill them by stopping them from feeding.

Which of the following, if true, most strongly supports the view that it would not be advisable to try to eradicate agricultural pests that go through a caterpillar stage by spraying croplands with the enzyme mentioned above?

--> 
 Premise:  This special enzyme, when ingested, can kill immature caterpillars.
 Ask:  Why isn't it advisable to eradicate immature caterpillars?
 Pre-thinking:  Now, why shouldn't we try to eradicate pests that go through immature caterpillar stage?
1) Immature caterpillars are harmless or even beneficial to the crops
2) spraying this enzyme may have some downsides. The enzymes may hurt crops more than immature caterpillars do

(A) Most species of caterpillar are subject to some natural predation. 
--> It helps, and may even lead us to think that if caterpillars have natural predators, then killing them would be redundant. 
This was not part of my pre-thinking options. Let's hold onto this one for now and see if we can find something better.

(B) Many agricultural pests do not go through a caterpillar stage.  
--> We are concerned with the ones that go through caterpillar stage.

(C) Many agriculturally beneficial insects go through a caterpillar stage.   CORRECT 
-->This matches our pre-thinking. If these pests are beneficial for the crops, we shouldn't kill them. 
Now, between A and C, C comes across as a much stronger option that supports not killing caterpillars.

(D) Since caterpillars of different species emerge at different times, several sprayings would be necessary. 
--> Doesn't touch core of the problem. Spraying enzymes regularly may or may not be a problem.

(E) Although the enzyme has been synthesized in the laboratory, no large-scale production facilities exist as yet. 
--> This kinda directs to the fact that 'farmer' doesn't have the enzyme to spray on his farm. But, the question focuses on why shouldn't the farmer spray, regardless of the availability of the enzyme.

Apk641 · Answer

C Is correct. Many agriculturally  beneficial  insects go through a caterpillar stage. insects go through a caterpillar stage. We do not want to kill beneficial insects. The wording in this makes it seem out of scope at first glance, but with a closer look we can see that by spraying crops we will kill both beneficial and non beneficial insects

egmat · Answer

This strengthen question asks us to find evidence supporting why using this enzyme as a pesticide would be  inadvisable . Let me walk you through the logical approach to solve this effectively.

Key Information from the Passage:

ALL  caterpillar species produce identical juvenile hormone
The enzyme stops hormone production → stops feeding → kills immature caterpillars
Scientists can synthesize this enzyme for pest control

Strategic Approach:

Step 1: Identify what we need 
We need a reason why spraying this enzyme would be a  bad idea  for pest control. Think about potential negative consequences or fundamental flaws with this approach.

Step 2: Analyze the universal effect 
The critical insight: Since the passage states "caterpillars of  all species " produce the identical hormone, the enzyme would affect  every single caterpillar  it touches - not just pest species.

Step 3: Evaluate answer choices 
(A) Natural predation exists → Doesn't create a problem with enzyme use
(B) Many pests aren't caterpillars → Limits scope but doesn't make it inadvisable
(C) Many beneficial insects are caterpillars →  This is the key!  We'd kill helpful insects too
(D) Multiple sprayings needed → Inconvenient but not fundamentally problematic
(E) No production facilities yet → Temporary logistical issue, not inherent problem

The Critical Insight: 
Choice (C) reveals the fundamental flaw: since the enzyme affects ALL caterpillars indiscriminately, we'd destroy beneficial insects (like pollinators) along with pests. This collateral damage makes the method inadvisable despite its effectiveness.
 Answer: C

Want to master the systematic framework for evaluating unintended consequences in strengthen/weaken questions? Check out the  complete solution on Neuron by e-GMAT , which includes 3 alternative approaches and a reusable pattern recognition technique for similar problems. Access detailed explanations for official questions with practice quizzes tailored to your weaknesses here on  Neuron .

Caterpillars of all species produce an identical hormone called "juven

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Caterpillars of all species produce an identical hormone called "juven

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