adkikani wrote:
Hi Experts,
Can you help me to distinguish if this is an assumption question or strengthen question? Furthermore, what does phrase - is not undercut - suggest?
I am presenting my analysis:
Some batches of polio vaccine used around 1960 were contaminated with SV40, a
virus that in monkeys causes various cancers.
This is a fact.
Some researchers now claim that
this contamination caused some cases of a certain cancer in humans,
mesothelioma.
This sentence is claim by researchers so it can be a belief of people other than author hence it is not main conclusion.
This claim is not undercut by the fact that a very careful survey
made in the 1960s of people who had received the contaminated vaccine found no
elevated incidence of any cancer, since ..
I took this whole sentence as fact and then I realized that only - This claim is not undercut by the fact - is the main conclusion. How can I avoid such traps? Further reading the argument also confused me since am i suppose to prove the fact that people in 1960 did not develop cancer in spite of getting contaminated vaccines. Since I wasn't able to understand argument in first place, I could not figure out correct OA.
Responding to a pm:
"not undercut" means "not weakened".
Premises:
Some polio vaccines in 1960s were contaminated by SV40.
Researchers claim that SV40 can cause mesothelioma.
Question stem: This claim is not undercut by the fact that a very careful survey made in the 1960s of people who had received the contaminated vaccine found no elevated incidence of any cancer, since___________.
Normally, if one would say "a very careful survey made in the 1960s of people who had received the contaminated vaccine found no elevated incidence of any cancer", this would weaken the claim of the researchers. The researchers say that SV40 could cause mesothelioma but since no elevated incidence was found, we would doubt the claim of the researchers.
But we need to find the reason this claim is not put in doubt by "no elevated incidence found".
Look at option (D): mesotheliomas take several decades to develop
The contaminated vaccine is given in 1960s. The survey was conducted in 1960s itself. If mesothelioma takes several decades to develop, we will not see an elevated incidence in the 60s decade itself. We will see an elevated incidence in later decades. Hence this option nicely completes the sentence.
All other options are irrelevant.
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86% (01:21) correct 
