When choosing the optimal portfolio on the efficient frontier, the investor should: Pick the point of risk tolerance appropriate for her and the choose the portfolio with the highest expected return for that level of risk. Pick the desired level of return and then choose the portfolio with the lowest level of risk for that return. Pick the portfolio with the highest Sharpe ratio and then choose the desired level of idiosyncratic risk to determine how much money to invest in this maximum Sharpe ratio portfolio. Pick the portfolio with the highest Sharpe ratio and then choose the desired level of systematic risk to determine how much money to invest in this maximum Sharpe ratio portfolio. Each of these methods is an equivalent way to solve the dual