pretty simple

This is a opposite answer... the official concludes that avoiding cheese will help avoid measles and other diseases... where as D says a defeciency in chees products make people more prone to measles

A : A is a conclusion from the premise which says children who avoid cheese products will avoid measles and chicken pox.. and then finally concludes that these children will avoid most childhood diseases.

- so if A were true the official's conclusion about children managing to avoid most diseases will be true: strengthen - out

B: this says that the data used to predict the outcome is correct... so it strengthen's the fact to some extent.. but if you are still not convinced.. : hold it

C : confirms that people who dont eat cheese products at school are usually the this way and dont abstain from cheese at school only : strengthen because the conclusion is based on the assumption that people who dont eat cheese will not fall sick

D : this says that people who generally dont eat cheese will have greater probability to contact measles.. so the author's conclusion that staying away from cheese helps prevent measles is wrong : weaken

E: If cheese products have bacteria that cause measles and other diseases, children will be protected if they abstain from eating cheese : strengthen

so the clear winner is D... hope this helps... btw why do you disagree?

When I read the sentence above, I have no idea what it means. I can only guess they intend the above to mean that those with a *diet* deficient in cheese products are more susceptible to measles or chicken pox infection. But the word 'deficiency' can mean two different things. It can mean a 'lack' or 'shortage' in something, but it can also mean a 'shortcoming' in something. That is, the above sentence could equally well mean that the cheese products themselves have some flaw or shortcoming which causes measles. That's how I interpreted the sentence on a first reading, and of course with that interpretation, this answer choice implies that those exposed to cheese products would then be more likely to contract measles.

So the writing here is so imprecise, answer choice D can mean two exactly opposite things. It's a badly written question, and no real GMAT question is ever so careless with language.
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"deficiency in cheese products" means "lack of cheese products in the diet"? Is this proper meaning of the statement? I disagree with this meaning.

The statement sounds like there is some problem with cheese products that is causing diseases. Hence D cannot be correct. Anyone else?
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