Final answer:
The question relates to the increasing diversity in elected officials, particularly the presence of women and minorities, which began to rise in the 1990s due to efforts by various organizations and political action committees.
Step-by-step explanation:
Since the 1990s, there has been a marked change in the makeup of elected officials in the United States. This period saw an increase in the diversity and representation of minorities and women in political positions. The National Organization for Women and the National Women's Political Caucus played significant roles in encouraging this shift, working to get more women involved in politics, to support their campaigns, and to elect them to office. The creation of political action committees like EMILY's List, which focuses on electing pro-choice Democratic women, further contributed to the larger presence of women in the U.S. House. Efforts by the Republicans to increase the number of Republican women in the House also underscore the ongoing changes. Still, as of recent Congresses, women and minorities remain underrepresented relative to their proportion in the general U.S. population, though progress has been noted in racial and ethnic diversity in these bodies.