Question

A news website is interested in knowing which other sites its users visit for their technology news, so it sends an email survey to 10,000 of its registered users selected at random. For what type of bias are the survey results at risk?

A.
The survey results are not at risk for any bias.
B.
The survey results are most at risk for undercoverage.
C.
The survey results are most at risk for nonresponse bias.
D.
The survey results are at risk for nonresponse bias and undercoverage.