Explanation:

The coefficient of variation (CV) is a standardized measure of dispersion that expresses the risk (standard deviation) per unit of mean return. This makes it useful for comparing the risk-adjusted performance of different investments, especially when their means differ significantly.

• Option A is correct because the CV directly measures the amount of risk (standard deviation) relative to the mean return.
• Option B describes the Sharpe ratio, which measures the mean excess return (return above the risk-free rate) per unit of risk, not the CV.
• Option C refers to the mean absolute deviation (MAD), which calculates the average of absolute deviations from the mean, not the CV.