The correct answer is C. Coefficient of variation.
A relative measure of dispersion is a measure of how spread out a set of data is relative to its mean. The coefficient of variation is a measure of relative dispersion that is calculated by dividing the standard deviation by the mean. It is expressed as a percentage and is often used to compare the variability of two or more sets of data with different means.
The standard deviation is a measure of how spread out a set of data is around its mean. It is calculated by taking the square root of the variance. The variance is a measure of how much the data points vary from the mean. It is calculated by taking the average of the squared deviations from the mean.
The coefficient of variation is a more robust measure of dispersion than the standard deviation because it is not affected by changes in the scale of the data. For example, if you have two sets of data, one with a mean of 10 and a standard deviation of 5, and the other with a mean of 100 and a standard deviation of 50, the standard deviation of the second set of data is twice as large as the standard deviation of the first set of data, but the coefficient of variation of the second set of data is the same as the coefficient of variation of the first set of data.