A college professor conducted a survey about students who have jobs by emailing all students at the university during the summer months until she collected responses from 100 students. In the survey, 42% of those who responded said they have jobs. In reality, 73% of the students at this university had jobs at the time of the survey. Which of the following best explains the difference in the two percentages?
The difference is due to voluntary response. Students are able to volunteer as a member of the sample.
The difference is due to response bias. Students who have jobs are likely to lie and say that they are unemployed.
The difference is due to undercoverage bias. The survey included only students who could respond to the email in a timely manner.
The difference is due to sampling variability. The results of a random sample shouldn't be expected to match the truth about the population every time.
The difference is due to nonresponse bias. Students who have jobs are less likely to be able to respond to the survey than students who are unemployed.