Critical Reasoning

In malaria-infested areas, many children tend to suffer several bouts of malaria before becoming immune to the disease. Clearly, what must be happening is that those children's immune systems are only weakly stimulated by any single exposure to the malaria parasite and need to be challenged several times to produce an effective immune response.

Which of the following, if true, most seriously undermines the explanatory hypothesis?

(A) Immediately after a child has suffered a bout of malaria, the child's caregivers tend to go to great lengths in taking precautions to prevent another infection, but this level of attention is not sustained.
(B) Malaria is spread from person to person by mosquitoes, and mosquitoes have become increasingly resistant to the pesticides used to control them.
(C) A certain gene, if inherited by children from only one of their parents, can render those children largely immune to infection with malaria.
(D) Antimalaria vaccines, of which several are in development, are all designed to work by stimulating the body's immune system.
(E) There are several distinct strains of malaria, and the body's immune response to any one of them does not protect it against the others.

Please explain each choice. Thank you

IMO E

In malaria-infested areas, many children tend to suffer several bouts of malaria before becoming immune to the disease. Clearly, what must be happening is that those children’s immune systems are only weakly stimulated by any single exposure to the malaria parasite and need to be challenged several times to produce an effective immune response.

All others seem out of context or not repleted to the discussion as we need to prove hypothesis is wrong. For making it wrong we have to find out the option which says the several bouts are not the same type of malaria but they are of different categories which happen due to exposure of the malaria parasite. (Of course this reasoning I found after looking into the choices.)
(E) There are several distinct strains of malaria, and the body’s immune response to any one of them does not protect it against the others.
So there are diff strains of Malaria. If the strains are different then the immunity system also has to be different accordingly. We can say when the child has not suffered with a particular strain of malaria it will not have the immunity. So multiple strains lead to several bouts of malaria .

But what is the assumption ( Please correct me if I am wrong )

Immune system is stimulated by the single exposure of malarial parasite and should be stimualted sveral times.

If we weakean this assumption we undermine the Hypothesis . What about If Immune system is stimulated by the antimalarial vaccacine ( D) and not by the several expoure to malarial parasite. This undermines the hypothesis.

Therefore IMO D

Please explain

SmarpanGamt wrote:But what is the assumption ( Please correct me if I am wrong )

Immune system is stimulated by the single exposure of malarial parasite and should be stimualted sveral times.

If we weakean this assumption we undermine the Hypothesis . What about If Immune system is stimulated by the antimalarial vaccacine ( D) and not by the several expoure to malarial parasite. This undermines the hypothesis.

Therefore IMO D

Please explain

I dont think while negating we can say so. First of all the premise does not say anything about antimalarial vaccine, Second these are still in development so least chances of using them on people, Third if you weaken it that means these vaccines are not useful but we cannot say these vaccine stimulate to cause the malaria. Because stimulating immunity will enhance the system not weaken the system, even the stimulation by exposure to MP works in a sense of enhancing the immunity system.

I dont think D is correct.

Let me put in this way :

Hypothesis :

Children Immune systme is only weakly stimulated by single MP and need to be challenge several time of effective immune system

WHat if their is some other cause of the above effective immune system, than the hypothesis fails.

If the Cause is " Anti malarial vaccacines"

Yes point is true ( E) that Several distinct of malaria is the cause not the single MP also fails the hypothesis.

First : Premise will not say other reasons for the cause.
Second : Some of which are in development but some are already in use.

Third: Vaccacines stimulates immune system not malaria.

@shovan Your point is correct that Vacaccine usage is not mentioned only its development is mentioned.

@shovan : Thanks for the discussion : I realize my mistake in reading the stimulus.