Research on Premarital Sex Indicates That Over the Past Century

Research on premarital sex indicates that over the past century,

A) increasing numbers of people engage in premarital coitus at younger ages.
B) Increasing numbers of people engage in premarital coitus but at older ages.
C) the highest rate of premarital coitus occurred in the sexual revolution of the 1960's with lower numbers before and since.
D) the difference between men and women has not changed.