15. The manufacturet of an over-the-counter pain reliever claims that its productbrings pain relief to headache sufferers in less than 3.5 minutes, on average. Tobe ablc to make this claim in its television advertisements, the manufacturerwas required to present statistical evidence in support of their claim. Themanufacturer reported that for a random sample of 50 headache sufferers, themean time to relief was 3.3 minutes and the standard deviation was 60 seconds.Find the rejection region for the test if testing at a= .05.
(A)Reject H0 ifz＜-1.96.
(B) Reject  H_{0 ifz＜-1.645.
(C)Reject  H0 ifz＜-1.282.
(D)Reject H0 ifz ＜ -1.96 or z ＞1.96.}