Question: A random sample of 25 employees of a local company has been measured. A 95% confidence interval estimate for the mean systolic blood pressure for all company employees is 123 - 139. Which of the following statements is valid?

a) 95% of the sample of employees has a systolic blood pressure between 123 and 139

b) If the sampling procedures were repeated many times, 95% of the resulting confidence intervals would contain the population mean systolic blood pressure.

c) 95% of the population of employees has a systolic blood pressure between 123 and 139.

d) If the sampling procedure were repeated many times, 95% of the sample means would be between 123 and 139.