问题如下：
Using the information in the following table, the sample standard deviation for VWIGX is closest to:
选项：
A.6.02%
12.04%.
24.54%
解释：
C is correct. The sample variance is defined as sum of the squared deviations from the sample mean divided by the sample size minus one, and the sample standard deviation equals the square root of the sample variance.
The sample variance is thus equals to 6.02. The square root of the sample variance is the sample standard deviation and equals to 24.54%.
A is incorrect because it is the sample variance for VWGIX, not its sample standard deviation.
B is incorrect because it represents the sum of the squared deviations from the mean, not the sample standard deviation.
算标准差必须是先算方差再开根号吗
