"It is best for the university to use the 90 questionnaires that were submitted as the final sample. Since the university selected a random sample of 120 students and only 90 responded, those 90 responses provide a representative sample of the opinions of this year’s freshman class. Starting over with a new sample or adding 30 more students to the sample could introduce bias into the results. Additionally, sending another email to the 30 students who did not respond may not be effective in increasing the response rate."
"Of the options provided, the best option would be to send another email to the 30 students who did not respond to the initial questionnaire, encouraging them to complete it. This would allow the university to increase the response rate and collect more comprehensive data. Starting over with a new sample of 120 students would be time-consuming and may not necessarily produce better results, since there is no guarantee that the new sample would have a higher response rate. Using the 90 questionnaires that were submitted as the final sample would not provide a representative sample of the entire freshman class, and choosing 30 more students at random and emailing them the questionnaire would not address the low response rate from the initial sample."
"It is best for the university to use the 90 questionnaires that were submitted as the final sample. Since the university selected a random sample of 120 students and only 90 responded, those 90 responses provide a representative sample of the opinions of this year’s freshman class. Starting over with a new sample or adding 30 more students to the sample could introduce bias into the results. Additionally, sending another email to the 30 students who did not respond may not be effective in increasing the response rate."