The risk-free rate of return is 4 percent, and the market return is 10 percent. The betas of Stocks A, B, C, D, and E are 0.85, 0.95, 1.20, 1.35, and 0.5, respectively. The expected rates of return for Stocks A, B, C, D, and E are 8 percent, 9 percent, 10 percent, 14 percent, and 6 percent, respectively. Which stock should a rational investor purchase?