The average annual retum over the period 1886-2006 for stocks that comprise the S&P 500 is 11.5%, and the standard deviation of returns is 20%. Based on these numbers what is a 95% confidence interval for 2007 returns? O A.-28.5%, 51.5% OB. - 14.25%, 25.75% OC. - 18.5%. 41.5% D. - 13.5% 36.5% tr Cakto select your answer de build your Type here to search i N % 3 4 5 & 6 KO 7 le tab Q W E R. T T Y Capsle