Medical researcher: As expected, records covering the last four years of ten major hospitals indicate that babies born prematurely were more likely to have low birth weights and to suffer from health problems than were babies not born prematurely. These records also indicate that mothers who had received adequate prenatal care were less likely to have
low birth weight babies than were mothers who had received inadequate prenatal care. Adequate prenatal care, therefore, significantly decreases the risk of low birth weight babies.
Which one of the following, if true, most weakens the medical researcher’s argument?
(A) The hospital records indicate that many babies that are born with normal birth weights are born to mothers who had inadequate prenatal care.
(B) Mothers giving birth prematurely are routinely classified by hospitals as having received inadequate prenatal care when the record of that care is not available.
(C) The hospital records indicate that low birth weight babies were routinely classified as having been born prematurely.
(D) Some babies not born prematurely, whose mothers received adequate prenatal care, have low birth weights.
(E) Women who receive adequate prenatal care are less likely to give birth prematurely than are women who do not receive adequate prenatal care.

Conclusion : "Adequate prenatal care, therefore, significantly decreases the risk of low birth weight babies."

We can say - Adequate Parental Care -> decrease risk of low birth weight babies.

I think ans will be Option A.

What is OA?

IMO B

premises :
premature del----->low birth wt babies----->health problem

ad. care-----> lless likely for low birth wt babies

conlusion : ad Par care----> low risk for low birth babies

mising link is : premature del

reaarange
ad P care---->less premature del---->low risk

only option B discuss that
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Can someone explain why the answer cant be D?

IMO ans is A.

The author's conclusion is "Adequate prenatal care, therefore, significantly decreases the risk of low birth weight babies". To destroy this argument choice A seems like the complete opposite of what the author concludes on pre natal care vis a vis birth weight.

that was really great explanation....

IMO B
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If you think you can,you can
If you think you can't,you are right.

this is a weaken question.

the conslusion is........

adequate prenatal care ==> low risk of weight

How does option (B) weaken this conclusion? can someone please explain.

b straight away hits the relationship

B
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lets start again

B is the best option for me