NO.PZ2018070201000077
问题如下：
Which of the following is the optimal portfolio for a individual investor according to the capital market theory?
选项：
A.
the combination of a risk-free asset and a risky asset with the highest expected return.
B.
the combination of a risk-free asset and a risky asset with the highest indifference curve.
C.
the combination of a risk-free asset and a risky asset with the highest capital allocation line slope.
解释：
B is correct.
Individuals' optimal portfolios is determined by different indifference curves, which delivers the highest utility. So CAL is tangent to the individual investor’s highest possible indifference curve.
以前的回答都是从optimal portfolio定义上说的，我当然知道optimal portfolios是CAL和无差异曲线的交点，正因为如此，无差异曲线和CAL有无数个交点吧，只要投资者能承受更大的风险和更高的回报。A和C都说无风险资产和带有最高收益的风险资产，最高的无差异曲线，那么多高算高，理论上可以无限向上吧。只有斜率是固定的，和最高斜率的组合，怎么就不对呢？
