Answer
Population is the collection of responses about the vaccination status from all the US adults.
Sample is the collection of responses from 12,082 adults surveyed.
Work Step by Step
The question of interest in the survey is the percentage who received an influenza vaccine among the US adults during the recent flu season.
So the population is the collection of responses about the vaccination status from all the US adults and the sample is the collection of responses from 12,082 adults surveyed.
