Is a standard deviation of 10 a large number indicating great variability,or is it small number indicating little variability? To answer this question correctly,one should look carefully at the value of the:

A) mean.
B) standard deviation.
C) coefficient of variation.
D) mean dividing by the standard deviation.

The coefficient of variation (C) is the correct answer because it is a measure that indicates the extent of variability in relation to the mean of the population. It is calculated as the ratio of the standard deviation to the mean, and it provides a standardized measure of dispersion of a probability distribution or frequency distribution. This is useful for comparing the degree of variation from one data series to another, even if the means are drastically different from each other.