A public health official reported that 60 percent of the

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?