Red blood cells in which the malarial-fever parasite resides are

Premise: Red blood cells in which malarial parasite resides are eliminated from a person after 120 days
Premise: Parasite can't travel to a new generation of red blood cells
[Assumption: Malarial parasite is completely eliminated from a person after 120 days]
Conclusion: Any fever that develops in persons more than 120 days after that person moved to a malaria-free region is not due to malarial parasite.
We can weaken this conclusion by showing that the fever that develops more than 120 days is indeed caused by malarial parasite although that person is moved to malarial-free region.
A. Out of scope by comparing malarial parasite and flu viruses.
B. Out of scope. The mosquito has nothing to do with the fever here.
C. This is a Shell Game. It does not weaken the conclusion because it mentions about the malarial symptoms that can can reappear within 120 days after the medication is discontinued.
D. Option D breaks the assumption by proving that malarial parasite is not eliminated because it travels to cells of spleen, which are less frequently eliminated from a person’s body than are red blood cells; therefore, malarial parasite can cause fever after a person is moved to a malarial-free region.
E. Out of scope.
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(A) The fever caused by the malarial parasite may resemble the fever caused by flu viruses.
This is not related to the argument
(B) The anopheles mosquito, which is the principal insect carrier of the malarial parasite, has been eradicated in many parts of the world.
This is just extra information.
(C) Many malarial symptoms other than the fever, which can be suppressed with antimalarial medication, can reappear within 120 days after the medication is discontinued.
This supports the theory that parasite remains for 120 days
(D) In some cases, the parasite that causes malarial fever travels to cells of the spleen, which are less frequently eliminated from a person’s body than are red blood cells.
This weakens the conclusion that parasite will die in at max 120 days.
What if it goes into cells of the spleen?.
(E) In any region infested with malaria-carrying mosquitoes, there are individuals who appear to be immune to malaria.
Again just extra information

phoenix08,
Option A can also weeken the conclusion. If 'The fever caused by the malarial parasite may resemble the fever caused by flu viruses' then it is possible that the fever may last for more than 120 days.

Any takers?

What we know of flu viruses from the argument? Nothing, The argument does not deal with Flu Viruses.

+1 for D because is the only choice that say us after 120 days is still malaria parasite the cause of fever.
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Option A would in a way strengthen the conclusion....that it may be flu and not malaria...in case the person suffers from Fever

D it is , although I did initially confuse with (C). However (C) does seem to trick us into taking an assumption which is not a part of the argument

I chose D

Conclusion: After 120 days if malaria reappear then its not due to malaria parasites.

Only option D says that Still the parasite causes the malaria which is not eradicated with medication because it sits safely in spleen.

Answer Choice D
This weakens the conclusion that parasite will die in at max 120 days.
What if it goes into cells of the spleen?.

Red blood cells in which the malarial-fever parasite resides are eliminated from a person’s body after 120 days. Because the parasite cannot travel to a new generation of red blood cells, any fever that develops in a person more than 120 days after that person has moved to a malaria-free region is not due to the malarial parasite.

Which of the following, if true, most seriously weakens the conclusion above?

(A) The fever caused by the malarial parasite may resemble the fever caused by flu viruses.
TRAP ANSWER. Argument does not talk about resemblance flu virus at all.

(B) The anopheles mosquito, which is the principal insect carrier of the malarial parasite, has been eradicated in many parts of the world.
OUT OF SCOPE. Does not affect the case in anyway.

(C) Many malarial symptoms other than the fever, which can be suppressed with antimalarial medication, can reappear within 120 days after the medication is discontinued.
IRRELAVANT

(D) In some cases, the parasite that causes malarial fever travels to cells of the spleen, which are less frequently eliminated from a person’s body than are red blood cells.
CORRECT . If Another source (spleen) through which a person can still catch malaria in malaria free region. Thus, the cause may still indirectly be the parasite, though not in the same carrier.

(E) In any region infested with malaria-carrying mosquitoes, there are individuals who appear to be immune to malaria.
IRRELEVANT. We are talking about people in malaria free regions.

KUDOS if this helps!

Hello experts!

Within C, is it wrong because of the "malarial SYMPTOMS" and "reappear within 120 days" parts?

The answer is speaking to symptoms. We don???t care about that. We want to know if someone definitively is capable of developing the disease after 120 days for the first time, NOT reappearing.

Red blood cells in which the malarial-fever parasite resides are eliminated from a person’s body after 120 days. Because the parasite cannot travel to a new generation of red blood cells, any fever that develops in a person more than 120 days after that person has moved to a malaria-free region is not due to the malarial parasite.

Which of the following, if true, most seriously weakens the conclusion above?


(A) The fever caused by the malarial parasite may resemble the fever caused by flu viruses. X

This is an irrelevant detail. We need to attack the idea that fevers that occur more than 120 days after ARE NOT due to malarial parasite. We can do so by showing that despite the elimination of the RBCs in which the parasite resides, these parasites somehow still cause the fever after 120 days.

(B) The anopheles mosquito, which is the principal insect carrier of the malarial parasite, has been eradicated in many parts of the world. X

Irrelevant.

(C) Many malarial symptoms other than the fever, which can be suppressed with antimalarial medication, can reappear within 120 days after the medication is discontinued. X

Careful. Trap choice. The key words to hone in on are 'OTHER THAN THE FEVER'. That takes us away from the focus: fevers.

(D) In some cases, the parasite that causes malarial fever travels to cells of the spleen, which are less frequently eliminated from a person’s body than are red blood cells.

CORRECT

(E) In any region infested with malaria-carrying mosquitoes, there are individuals who appear to be immune to malaria. X

Irrelevant.
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Conclusion: Because the parasite cannot travel to a new generation of red blood cells, any fever that develops in a person more than 120 days after that person has moved to a malaria-free region is not due to the malarial parasite.
Let's weaken it!


If the fever of the malarial parasite resembles the fever of the flu virus, then the person getting a fever after 120 days is maybe due to the flu virus and NOT the malarial parasite. Bit strengthener. Eliminate A


If the mosquito is eradicated from many parts of the world, then the fever is due to some other reason and NOT a malarial parasite. Again a strengthener. Eliminate B


Classic GMAT option with a twist Our conclusion is concerned with fever but this option is telling us about symptoms OTHER THAN FEVER. Secondly, as per the conclusion, 'the fever develops in a person MORE THAN 120 days after that person has moved' but this option is telling us that symptoms 'reappear WITHIN 120 days'. Eliminate C


If the parasite can travel to cells of the spleens, which are not eliminated from the body, then this is the reason why a person gets fever because of the malarial parasite. Nice clear weakener. Keep D


Again a strengthener. If individuals are immune to malaria, then the fever is due to some other thing! Eliminate E
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