Which one of the following is the positive square root of the $\mathrm{variance}$?

• A. $\mathrm{Median}$
• B. $\mathrm{Mode}$
• C. $\mathrm{Standard} \mathrm{deviation}$
• D. $\mathrm{Mean}$

Answer: (C)

Verified step by step guidance

1. Understand that the variance of a data set measures the average squared deviation from the mean, which means it is expressed in squared units.
2. Recall that the square root of the variance is called the standard deviation, which brings the measure back to the original units of the data.
3. Recognize that the median and mode are measures of central tendency, not measures of spread or variability, so they are not related to the square root of the variance.
4. Recall that the mean is also a measure of central tendency and does not represent the square root of the variance.
5. Therefore, conclude that the positive square root of the variance is the standard deviation.