In finance, risk is commonly measured by calculating the:

In finance, risk is commonly quantified as the volatility or dispersion of an investment's returns. Statistical measures are employed to capture this variability, providing investors with a numerical understanding of potential fluctuations.

• C: Standard deviation is the correct answer and the most widely used statistical measure of risk in finance. It quantifies the average amount by which individual data points (returns) deviate from the mean (average return). A higher standard deviation indicates greater volatility and, consequently, higher risk, as it suggests that actual returns are likely to vary more significantly from the expected return.
• A: Mean represents the average or expected return of an investment, not its risk. It is a measure of central tendency.
• B: Variance is also a measure of dispersion, calculated as the average of the squared differences from the mean. While closely related to standard deviation (standard deviation is the square root of variance), standard deviation is generally preferred because it is expressed in the same units as the returns, making it more intuitive and easier to interpret.
• D: Kurtosis measures the 'tailedness' of the distribution of returns, indicating the frequency of extreme positive or negative outcomes. While it provides insight into 'tail risk,' it is not the primary or most common measure of overall investment risk; standard deviation holds that distinction.