You are evaluating the risk-return trade-off of four stocks. The data below shows the expected return and standard deviation of each stock. Which stock offers the best risk-return trade-off based on Sharpe Ratio? (Assuming that you can also invest in Treasury bills to earn a risk-free rate of 3%. Stock B D 16% 12% 13% 15% expected return standard deviation 8% 11% 12% 14% stock B O stock D O stock A stock