"considering the increased frequency with which young women in the 1920s engaged in sexual behavior like dating and petting, in what way were these women still upholding traditional notions of morality?

Women involved in the dating and petting encounters were free to decide if they wanted to be involved in sexual activities.

Explanation:

In the 1920s, some women did really like the idea of being free, showing the best and sexiest part they could offer, however, in the common parties at that moment in history they were free to experiment and act as they pleased. Therefore, some of them simply assist to the meetings to have a good time with their friends, to dance, if they wanted they could kiss someone, or even go beyond. Some of these women were still upholding the traditional notions of morality, because they simply wanted to be in a good environment having fun with some people, without having any physical contact with the other participants, or drinking, or smoking they were just enjoying the young epoch.

i believe the answer is:   psychological  experiment

in this experiment, wilhelm wundt became the first person that implement scientific method in analyzing the pyschological phenomenon.

due to this result, wilhelm wundt also able to make psychology to be acknowledged as a separate scientific field from biology.