A researcher wants to know how dog owners in the United States feel about establishing a law requiring individuals who own pit bulls to obtain insurance for their dog. The researcher mails a survey to a random sample of 5,000 owners out of all registered dog owners in the
US. A total of 2,389 out of the 5,000 respond and 22% say they favor the law. Which of the following is true based on this information?

Select one:

a. There is sufficient evidence that the percentage of all dog
owners who say they favor insurance for pit bulls is close to
22% because random sampling was used.

b. There is sufficient evidence that the percentage of all dog
owners who say they favor pit bull owners obtaining insurance for their dog is close to 22% because less than half of those who were mailed the survey responded.

c. The results of this survey are invalid because the survey was
mailed and not a face-to-face interview.

d. There is evidence of nonresponse bias in the survey results.

e. There is strong evidence of convenience response bias in the survey results.