A researcher wants to know whether home-schooled students in the United States prefer to learn at home versus at a public school with other students. The researcher mails a survey to a random sample of 7,500 students out of all home-schooled students in the US. A total of 4,195 out of the 7,500 respond and 39% say they prefer to learn at home. Which of the following is true based on this information?

There is evidence of nonresponse bias in the survey results.
There is strong evidence of convenience response bias in the survey results.
There is sufficient evidence that the percentage of all home-schooled students who say they favor learning at home is close to 39% because random sampling was used.
There is sufficient evidence that the percentage of all home-schooled students who prefer to learn at home is close to 39% because more than half of those who were mailed the survey responded.
The results of this survey are invalid because the survey was mailed and not a face-to-face interview.