Paper lice feed on microscopic spores of a certain fungus that grows

Question

Paper lice feed on microscopic spores of a certain fungus that grows primarily in damp areas; when these fungal spores are present on the pages of a book, the paper lice will also ingest the paper comprising the pages unless the paper is treated with insecticide. However, many rare and valuable books are too fragile to be treated with insecticide. Dehumidifying the environment to minimize dampness will allow rare books that cannot be treated with insecticide to be stored without risking damage from paper lice.

The argument depends on which of the following assumptions?

A. Paper lice can be prevented from entering an area that is being dehumidified.

B. Treating rare books with insecticide will cause more significant damage than that caused by paper lice.

C. After the fungus has been eliminated, fungal spores do not remain in any significant quantity.

D. It is possible to store rare books in a dry environment without causing the pages to become brittle and crack.

E. No other insects, aside from paper lice, typically feed on the paper used to create books.

sayan640 · Accepted Answer

VeritasKarishma 
 chetan2u 
 mikemcgarry 
 GMATNinja

Can you pls check my explanation...
If you negate option A , it become s "Paper lice can not be prevented from entering an area that is being dehumidified."
Then also the conclusion "Dehumidifying the environment to minimize dampness will allow rare books that cannot be treated with insecticide to be stored without risking damage from paper lice. "
can follow. What if there are no fungal spores left in the area which paper lice can feed on ? Then paper lice may not thrive and the rare books can be stored without risking damage from paper lice .
The conclusion can follow after negating assumption. So A is not correct.

If option C is negated , it becomes "After the fungus has been eliminated , the fungal spores remain in significant quantity."
Then the conclusion "Dehumidifying the environment to minimize dampness will allow rare books that cannot be treated with insecticide to be stored without risking damage from paper lice. "
can not follow. Because even after de humidification , fungal spores can remain in significant quantity and that may allow paper lices to feed on fungal spores and the conclusion i.e books can be stored without risking damage " may not follow.

KarishmaB · Answer

Responding to a pm:

Paper lice feed on "spores" of a certain fungus so if books have spores, the lice eat the paper too.
The fungus grows in damp areas.
Paper can be treated with insecticide to avoid this damage.
But many rare books cannot stand insecticide treatment.

Conclusion: 
Dehumidifying will allow rare books to be stored without risking damage from paper lice.

Note that the conclusion is talking about damage from paper lice only, not any other kind of damage. So the assumption has to deal with damage from paper lice only.

A. Paper lice can be prevented from entering an area that is being dehumidified.

Irrelevant. We aim to get rid of the spores on the paper that they feed on. If we are able to do that, it doesn't matter whether lice are present or not. They will not eat the paper of the books.

B. Treating rare books with insecticide will cause more significant damage than that caused by paper lice.

Irrelevant. We are only concerned about whether dehumidifying will avoid damage by paper lice or not.

C. After the fungus has been eliminated, fungal spores do not remain in any significant quantity.

Correct. We are given that the fungus grows in humid environments. Dehumidifying will take care of the fungus but will it take care of the spores of the fungus too? We don't know. We are assuming that it will and that is why we are concluding that lice will not eat paper anymore.

D. It is possible to store rare books in a dry environment without causing the pages to become brittle and crack.

Irrelevant. We are only concerned about whether dehumidifying will avoid damage by paper lice or not. What other damage dehumidifying can cause doesn't matter. We are not concluding that books will be safe if we dehumidify. We are only concluding that books will be safe from paper lice.

E. No other insects, aside from paper lice, typically feed on the paper used to create books.

Again, irrelevant. Any other kind of damage has no relevance to our argument.

Answer (C)

Sneha333 · Answer

Please Explain why D cannot be correct?

rish2708 · Answer

D can't be an answer because the argument exclusively is about protecting the books from Paper Lice. 
Whether they would go brittle or get torn apart does not address the concern that they will be protected from Paper Lice

medic19 · Answer

Not an expert, but agreed that it is down to A and C. But look at the main part of the argument: "risking damage from paper lice". What do lice do? They feed on fungal spores and fungus grows in damp areas. Accordingly, it is not a case of simply reducing the fungus, but rather eradicating it completely. The risk is therefore still there. This answer is better as it deals with the passage as a whole, including the argument and the premise. 'A' only deals with the lice - but what is the lice can fly in and there is no fungus? They would present no danger whatsoever.

rish2708 · Answer

Thanks for your reply!
I agree to this point but option C says reduce the fungus spores significantly, it's not over.
So, then also these Lices can attack right? The situation seems still vulnerable.

What I perceived was that if dehumidification is there Lices won't enter and obviously fungus would decrease because they grow only in dampened areas.

Regards,
Rishav

KarishmaB · Answer

Yes, this is perfectly correct.

bae · Answer

Conclusion: Dehumidifying the environment to minimize dampness will allow rare books that cannot be treated with insecticide to be "stored" "without risking damage" from paper lice. Evidence/Premise: 1 Paper" lice" feed on microscopic "spores" of a certain fungus that grows primarily in "damp" areas; 2 these fungal "spores" are present on the pages of a book, the paper lice will also ingest the paper comprising the pages unless the paper is treated with insecticide. 3 "rare" and valuable books are too fragile to be treated with insecticide. Pre Assumption : Dehumid will allows the 1.spore not to grow and 2.kill the lice/fungi 3.Dehumid can work in damp area 4.remove risk of storage situation: Humid-> Spore -> Lice -> paper eaten -> induce risk of storage

A. Paper lice can be prevented from entering an area that is being dehumidified. 1, Half-answered solution, ok, so the lice has been prevented , but the spore remains, then lice comes, and prevent ... repeated vicious cycle... problem not solve.... (no gap closed, this only talks about the conclusion, what closes the gap and the evidences/premises?

) 2,Negate: paper lice cannot be prevented (how about the spore, and the risk of storage? the conclusion asking to attack store and spore) C. After the fungus has been eliminated, fungal spores do not remain in any significant quantity. 1, OK, spore eliminated, most likely won't attract lice. 2, Negate: After fungi eliminated, fungi spore remain significant ( This answered the gap, since conclusion asking to attack store and spore )

Socalsurfer2020 · Answer

Here’s the gist:

Logic: Humidity allows fungus to grow and fungus creates spores. The paper lice eat the spores (NOT the fungus) and, by consequence, consume the paper.

Plan: Reduce the humidity to reduce the fungus to reduce the consumption of the paper.

What is missing in the logic of the plan? Well, for the plan to work, the spores have to be eliminated (or at least not remain in high quantities once the fungus is gone).

Choice C addresses this head on.

Posted from my mobile device

doeadeer · Answer

Excerpts from the Official Explanation:
A) Keeping the paper lice out of the area isn’t strictly necessary. They only need to be prevented from eating the books, not from getting near the books.

(B) This answer supports the idea that treating rare books with insecticide is dangerous. However, the argument’s conclusion isn’t that insecticide is dangerous; it’s that dehumidification will protect the books from lice. Whether insecticide is dangerous has no bearing on whether dehumidification will work.

(C) CORRECT. The argument states that paper lice eat fungal spores and thereby damage books. However, it isn’t clear from the argument that dehumidification will eliminate the spores; the argument only suggests that dehumidification will keep the fungus from growing further. For dehumidification to work as intended, it needs to not only eliminate the fungus, but also eliminate the spores that the paper lice feed on.

(D) If dehumidification damages rare books, it may not be a good method to use in general. However, the conclusion only states that it will protect rare books from paper lice. A method doesn’t have to be completely successful in every way to be successful in protecting the books from lice.

(E) The conclusion specifically states that the dehumidification method will protect books from paper lice. The actions of other insects do not bear on whether the method will work on paper lice.

krishnakumar2 · Answer

D is talking about dry environment and it's not known or given in D that humid environment is wet environment and vice versa humidity can be in dry environment too , and wetness of the environment isn't related to humidity (according to limited question conditions )

And see In option C it's talking about the spores upon which that paper lice feeds upon so it's more necessary to eliminate the food not the plate(the fungus) first

Posted from my mobile device

happypuppy · Answer

D isn't correct because it talks about things that are out of context.
For, ex: All of the below statements don't talk about the point of concern, the env and the lice or the damage because of that.
It is possible to store rare books in a dry environment without causing the pages to become brittle and crack.
Or
It is possible to store rare books in a dry environment without causing the pages to become dull.
OR
It is possible to store rare books in a dry environment without causing the pages to become shiny.
OR
It is possible to store rare books in a dry environment without causing the pages to become hard and rough.

Crytiocanalyst · Answer

A. Paper lice can be prevented from entering an area that is being dehumidified.
We are not in aposition whether it is the only factor that's affecting the same

B. Treating rare books with insecticide will cause more significant damage than that caused by paper lice.
We are not in a position to determine whether the damage is equal or unequal

C. After the fungus has been eliminated, fungal spores do not remain in any significant quantity.
Yes this can be a reason that the fungus is getting eleminated

D. It is possible to store rare books in a dry environment without causing the pages to become brittle and crack.
We are not exactly sure whether other factors have no realistic effect

E. No other insects, aside from paper lice, typically feed on the paper used to create books.
Here to we are given no light from the given argument
Hence IMO C

rvgmat12 · Answer

OE:

(1) Identify the Question
The word assumption in the question indicates that this is a Find the Assumption question.

(2) Deconstruct the Argument
Paper lice feed on fungal spores that grow on books; this causes damage to the books. Ordinarily, this is prevented by treating the books with insecticide. However, some books cannot be treated with insecticide. The argument proposes dehumidifying the environment in order to protect these books from paper lice, since the fungus that creates the spores only grows in damp areas.

Here is one possible way to map the argument.

Spores on books

Lice eat spores → also eat books

Insecticide: lice can’t eat, but hurts books

(3) State the Goal
The goal is to find a statement that must be true in order for the conclusion to make logical sense. In this case, the right answer will describe a condition that must hold in order for dehumidifying to successfully protect the books from lice.

(4) Work from Wrong to Right

(A) Keeping the paper lice out of the area isn’t strictly necessary. They only need to be prevented from eating the books, not from getting near the books.

(B) This answer supports the idea that treating rare books with insecticide is dangerous. However, the argument’s conclusion isn’t that insecticide is dangerous; it’s that dehumidification will protect the books from lice. Whether insecticide is dangerous has no bearing on whether dehumidification will work.

(C) CORRECT. The argument states that paper lice eat fungal spores and thereby damage books. However, it isn’t clear from the argument that dehumidification will eliminate the spores; the argument only suggests that dehumidification will keep the fungus from growing further. For dehumidification to work as intended, it needs to not only eliminate the fungus, but also eliminate the spores that the paper lice feed on.

(D) If dehumidification damages rare books, it may not be a good method to use in general. However, the conclusion only states that it will protect rare books from paper lice. A method doesn’t have to be completely successful in every way to be successful in protecting the books from lice.

(E) The conclusion specifically states that the dehumidification method will protect books from paper lice. The actions of other insects do not bear on whether the method will work on paper lice.

Ro_007 · Answer

dehumidification prevents fungal growth due to lack of humidity right ? where does the fungal spore come from if there is no fungal growth in the first place ?

this is why I eliminated C. what am I missing or stretching beyond the bounds of the argument ? D was the only sensible option I had to go with since it spoke about books getting destroyed.

KarishmaB

KarishmaB · Answer

Currently there is fungus and hence fungal spores too (fungus produce those to reproduce). Once dehumidification is done, fungus will disappear but will fungal spores? Do they also get killed without moisture? We are not given. Just like in the case of bugs, insecticides kill the insects but may not kill the bugs' eggs (which are resilient). What if spores remain? If they do, the books may keep getting eaten by lice even after dehumidification (till spores remain).

As for (D), as I said in my solution above,  the conclusion is talking about damage from paper lice only, not any other kind of damage. So the assumption has to deal with damage from paper lice only. ANY other kind of damage is outside the scope of this argument.

Paper lice feed on microscopic spores of a certain fungus that grows

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Paper lice feed on microscopic spores of a certain fungus that grows

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