A research wishes to test whether a dietary supplement has a

A research wishes to test whether a dietary supplement has any effect on blood pressure against the default that it has no effect. The blood pressure of 25 volunteers is taken both before and after two months on the supplement. Using the diagram shown here, select the setup of the null and alternative hypothesis for this test is Note: Subscript (1) refers to before. Subscript (2) refers to after. Subscript \"d\" implies mean of differences.

A Choice I B Choice II C Choice III D Choice IV E Choice V

Solution

\"before and after\" implies paired test, mu_d will be used.

option II is correct.