A 2002 Gallup Survey Interviewed by Phone a Random Sample

Multiple Choice

A 2002 Gallup survey interviewed by phone a random sample of 474,195 U.S. adults. Participants were asked to describe their work status and to report their height and weight (to determine obesity based on a body mass index greater than 30) . Gallup found 24.9% obese individuals among those interviewed who were employed (full-time or part-time by choice) , compared with 28.6% obese individuals among those interviewed who were unemployed and looking for work.
What is the best description of the sample in this study?

A) Simple random sample
B) Stratified sample
C) Voluntary response sample
D) Cohort