问题如下：
The following table shows various statistics for Portfolios 1, 2, and 3.
Compared with a normal distribution, the distribution of returns for Portfolio 3 most likely:
选项：
A. is less peaked.
B. has a greater number of extreme returns
C. has fewer small deviations from its mean.
解释：
B is correct.
Portfolio 3 has positive excess kurtosis (i.e., kurtosis greater than 3), which indicates that its return distribution is leptokurtic, is more peaked than normal, and has fatter tails. The fatter tails mean Portfolio 3 has a greater number of extreme returns.
这道题为什么不选择b，怎么判断positive negative Skewness
