According to the Empirical Rule, Which of the Following Is $68 \%$

Multiple Choice

According to the empirical rule, which of the following is the approximate percentage of measurements in a data set (provided that the data set has a bell-shaped distribution) that fall within two standard deviations of their mean?

A) $68 \%$ .
B) $75 \%$ .
C) $95 \%$
D) $99 \%$ .