The practice which is not sound in conducting individuales is C) conducting in-person interviews and telephone interviews in the same poll.
In-person interviews deliver the most representative results. Telephone surveys provide a good alternative but they need using a larger sample.
I can’t see any possible options but secondary sources and online sources should be double checked and avoided if possible. few secondary sources are trustworthy like textbooks
<span>A. A club in Harlem for african amercians
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