The range and standard deviation of a distribution are
a.
measures of central tendency
b.
measures of variability
c.
types of transformed scores
d.
types of percentiles

The answer is B: measures of variability.

The range and standard deviation of a distribution are measures of variability.

Explanation:

Range refers to the difference between the lowest and highest values of a set of data. Its formula is the maximum value minus the minimum value in the set of data.

Standard deviation measures the dispersion of a set of data in relative to its mean. It is a measure of how numbers are spread out. It is calculated as the square root of the variance.

B.  measures of variability                        

Explanation:

Range: Range is a statistical measure of variance.

Formula of calculating range is:

                     Range= { (highest score-lowest score) + 1 }

Example: Highest score is 80; the lowest score is 35, then range will be

                     Range= {(80-35) +1}

                                = 46

Standard deviation: It is the score around the mean of a distribution. It measures the tendency with which a set of scores is distributed around an average measure of variability.