问题
单项选择题
With respect to the units each is measured in, which of the following is the most easily directly applicable measure of dispersion The:（）
A. standard deviation.
B. variance.
C. covariance.
答案
参考答案：A
解析：
The standard deviation is in the units of the random variable itself and not squared units like the variance. The covariance would be measured in the product of two units of measure.
