A December 2013 Gallup Poll of 13,186 Nationally Representative Adults

Multiple Choice

A December 2013 Gallup poll of 13,186 nationally representative adults found that 8.9% reported being sick with a cold. In its report, Gallup warned that, "In addition to sampling error, question wording and practical difficulties in conducting surveys can introduce error or bias into the findings of public opinion polls." Which of the following sources of uncertainty is taken into account when computing the margin of error of the confidence interval?

A) Question wording
B) Response bias
C) Nonresponse
D) Sampling error