Most Experts Recommend College Students Get at Least 8 Hours

Most experts recommend college students get at least 8 hours of sleep per night. You collect a random sample of 112 students at your college and ask how many hours of sleep they got last night. The sample mean amount of sleep last night was 7.6 hours, with a sample standard deviation of 2.1 hours. The sample distribution of hours of sleep was slightly skewed right. Does this provide evidence that students at your college are getting less than the recommended amount of sleep per night?
-Suppose that instead of measuring the amount of sleep each student got last night, you measured whether each student got at least 8 hours of sleep last night in your sample. Could you use these data to carry out a one-sample t-test to determine if students at your college are getting less than the recommended amount of sleep per night?

A) No, since whether each student got at least 8 hours of sleep last night is a categorical variable.
B) Yes, since we know whether each student got less than the recommended amount of sleep.
C) No, since the sample size is too small.
D) Yes, since we can calculate the proportion of students who got less than the recommended amount of sleep.