单选题 When creating intervals around the mean to indicate the dispersion of outcomes, which of the following measures is the most useful? The

A、

A. variance.
B、

B. median.
C、

C. standard deviation.

【正确答案】 C

【答案解析】The standard deviation is more useful than the variance because the standard deviation is in the same units as the mean. The median and mode do not help in creating intervals around the mean.