A researcher conducting a telephone survey is concerned about possible sources of bias. Of the following, which is the best example of nonresponse bias?

The wording of the questions in the survey leads people to respond in a certain way.

People might be uncomfortable with the survey questions and, as a result, might not always respond to those questions truthfully.

Many of the people selected to participate in the survey who do not respond might have opinions different from those who do respond.

People without telephones are overlooked in the sampling procedure used to determine who is surveyed.