A. which measure of variation is preferred when the mean is used as a measure ofâ center?

The standard deviation is a measure that is used to quantify the amount of variation or dispersion of a set of data values from the mean.

A low standard deviation indicates that the data points tend to be close to the mean of the set, while a high standard deviation indicates that the data points are spread out over a wider range of values.

Therefore, the measure of variation that is preferred when the mean is used as a measure of center is standard deviation.