Respuesta :
I think "D) a brochure from the respiratory information council at Johns Hopkins University" is the answer.
The source which would provide the most bias-free information about second hand smoke as a trigger for Asthma is; Choice D;
- a brochure from the respiratory information council at Johns Hopkins University.
Obtaining bias-free information
For every source of information regarding the topic in discuss, it follows that the source may be in favour of or against the topic in discuss.
On this note, a third-party body is trusted for the supply of bias-free information regarding such topic in discuss. Such trusted source in this context is the respiratory information council at Johns Hopkins University.
Read more on bias-free information;
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