问题如下图：这个真的需要用公式吗，感觉计算协方差的计算量那么大，没有捷径可以走吗
选项：
A. 
B. 
C. 
解释：
NO.PZ2018070201000067 问题如下 The return projections have been ma Eunice. analyst from investment company, for eaof the assets with the same probability of occurrence, whicombination of two equally-weighteassets hlowest versification effect? A.Asset A anAsset B.Asset B anAsset C.Asset A anAsset C is correct.We calso use the calculator to measure the correlation. The correlation between asset B anasset C is -1, between A anB is 0.5, anbetween A anC is -0.5, the higher correlation, the worse versification. -0.5 和 -1 为什么选-0.5呢？不是-1最分散？
NO.PZ2018070201000067 问题如下 The return projections have been ma Eunice. analyst from investment company, for eaof the assets with the same probability of occurrence, whicombination of two equally-weighteassets hlowest versification effect? A.Asset A anAsset B.Asset B anAsset C.Asset A anAsset C is correct.We calso use the calculator to measure the correlation. The correlation between asset B anasset C is -1, between A anB is 0.5, anbetween A anC is -0.5, the higher correlation, the worse versification. 表格含义是什么，如何使用计算器计算，解题思路是怎样的
NO.PZ2018070201000067问题如下The return projections have been ma Eunice. analyst from investment company, for eaof the assets with the same probability of occurrence, whicombination of two equally-weighteassets hlowest versification effect? A.Asset A anAsset C.B.Asset B anAsset C.C.Asset A anAsset B.C is correct.We calso use the calculator to measure the correlation. The correlation between asset B anasset C is -1, between A anB is 0.5, anbetween A anC is -0.5, the higher correlation, the worse versification. AB和AC的correlation分别是0.5和-0.5，为什么选AB？和他们方向相关吗？怎么理解
NO.PZ2018070201000067 问题如下 The return projections have been ma Eunice. analyst from investment company, for eaof the assets with the same probability of occurrence, whicombination of two equally-weighteassets hlowest versification effect? A.Asset A anAsset B.Asset B anAsset C.Asset A anAsset C is correct.We calso use the calculator to measure the correlation. The correlation between asset B anasset C is -1, between A anB is 0.5, anbetween A anC is -0.5, the higher correlation, the worse versification. RT
NO.PZ2018070201000067 问题如下 The return projections have been ma Eunice. analyst from investment company, for eaof the assets with the same probability of occurrence, whicombination of two equally-weighteassets hlowest versification effect? A.Asset A anAsset B.Asset B anAsset C.Asset A anAsset C is correct.We calso use the calculator to measure the correlation. The correlation between asset B anasset C is -1, between A anB is 0.5, anbetween A anC is -0.5, the higher correlation, the worse versification. 依照ta的计算器规则，在调动2nSTAT的时候页面只出现ln,再翻页的话就是error2，请问操作有什么问题吗？谢谢
