A certain characteristic in a large population has a distribution that is symmetric about the mean m. If 68 percent of the distribution lies within one standard deviation d of the mean, what percent J of the distribution is less than m +d ? Select the correct option:  A) 16 %  B) 32 %  C) 48 %  D) 84 %  E) 92 %

Rationale: "d the prompt says that 68 % of the population lies between m - d and m + d . thus , 32 % of the population is less than m - d or greater than m + d . since the population is symmetric , half of this 32 % is less than m - d and half is greater than m + d . thus , j = ( 68 + 16 ) % or ( 100 - 16 ) % of the population is less than m + d . d"
Answer: D