Suppose the heights of the members of a population follow a normal distribution. If the mean height of the population is 68 inches and the standard deviation is 4 inches, 68% of the population will have a height wighin which of the following ranges?

A. 56 inches to 80 inches
B. 60 inches to 76 inches
C. 64 inches to 72 inches
D. 52 inches to 84 inches