(1 point) Suppose a group of 900 smokers (who all wanted to give up smoking) were randomly assigned to receive an antidepressant drug or a placebo for six weeks. Of the 417 patients who received the antidepressant drug, 47 were not smoking one year later. Of the 483 patients who received the placebo, 33 were not smoking one year later. Test the null hypothesis Ho : (P1 - P2) = 0 against the alternative hypothesis Ha : (P1 - P2) # 0. Use a = 0.1 (a) The rejection region is | z| > (b) The test statistic is Z = The final conclustion is O A. There is not sufficient evidence to reject the null hypothesis that (p1 - p2) = 0. O B. We can reject the null hypothesis that (p1 - p2) = 0 and accept that (p1 - p2) # 0