问题如下图：
请问A和B选项是不是都是对的?感觉A和B表述刚好是相反的，如果B对，那A应该也是对的吧?麻烦老师解释一下，A为什么不对?
选项：
A. 
B. 
C. 
D. 
解释：
NO.PZ2018062001000003问题如下The characteristic of a return stribution is frequent small gains anseverextreme losses. Whiof the following options is correct?A.The stribution ha positive skewness, anthe meis greater ththe mean.B.The stribution ha negative skewness, anthe meis smaller ththe mean.C.The stribution ha positive skewness, anthe meis smaller ththe mean.We fine tha stribution with frequent small gains ana few extreme losses is a negative-skewestribution. The characteristiof a negative skewestribution are: long tail on the left si an mo me mepositive是mean比 mean大，negative不就是mean比mean小吗？
NO.PZ2018062001000003 问题如下 The characteristic of a return stribution is frequent small gains anseverextreme losses. Whiof the following options is correct? A.The stribution ha positive skewness, anthe meis greater ththe mean. B.The stribution ha negative skewness, anthe meis smaller ththe mean. C.The stribution ha positive skewness, anthe meis smaller ththe mean. We fine tha stribution with frequent small gains ana few extreme losses is a negative-skewestribution. The characteristiof a negative skewestribution are: long tail on the left si an mo me me 如果是左偏不就是右尾长吗？右尾长不就是右边有极端值吗？
NO.PZ2018062001000003 The stribution ha negative skewness, anthe meis smaller ththe mean. The stribution ha positive skewness, anthe meis smaller ththe mean. We fine tha stribution with frequent small gains ana few extreme losses is a negative-skewestribution. The characteristiof a negative skewestribution are: long tail on the left si an mo > me> mean老师可以画个图吗？我总是很难记住，左倾和右倾的图，这三个值的大小关系，老师可以分享一下记忆的方法吗？谢谢
NO.PZ2018062001000003 ...requent small gains ana few extreme losses这个描述的话，afew extreme loses 指的是左侧的细尾吗？
