Amethod of dispersion that gives us an overall picture of the gap between all the data within a data set is
a. range.
b. inter-quartile range (q3 – q1).
c. mean.
d. standard deviation.
e. coefficient of correlation

The correct answer is letter "D": Standard deviation.

Explanation:

Standard deviation is a measure used to count the deviation or dispersion of a group of numeric data. In Business, the standard deviation is a measure applied to the annual rate of return of an investment to measure the investment's volatility. Every time a stock or a mutual fund is purchased their  expected return is weighted against their inherent risk. The past gain or losses of investment is easy to look up but gauging is more complex.