Based on survey results, the mean amount of credit card debt for U.S. adults under 35 is $8,724. This point estimate would be unbiased and most accurate if the survey were based on which of the following?

A national television news station poll with 3,500 responsesA random sample of 2,800 U.S. adults under 35A random sample of 3,000 U.S. college studentsA random sample of 1,500 U.S. adults under 35- unanswered