Each of the 110 students in a statistics class selects a random sample of 35 Quiz scores from a population of 5000 scores. They are not given the population mean and standard deviation. Using these data, each student then constructs a 90% confidence interval for µ, the average Quiz score in the population of 5000 students. Which of the following conclusions is correct?

a. The widths of the 110 confidence intervals will be equal.

b. About 10% of the sample means will not be included in the confidence intervals.

c. About 90% of the confidence intervals will contain µ.

d. About 90% of the data will be found in these confidence intervals.