Answer: kurgans (burial mounds) of the Eurasian steppes. The hypothesis suggests that the Indo-Europeans, a nomadic culture of the Pontic-Caspian steppe (now part of Eastern Ukraine and Southern Russia), expanded in several waves during the 3rd millennium BC.
Explanation:
The most widely accepted proposal about the location of the Proto-Indo-European homeland is the steppe hypothesis, which puts the archaic, early and late PIE homeland in the Pontic–Caspian steppe around 4000 BC. The leading competitor is the Anatolian hypothesis, which puts it in Anatolia around 8000 BC.
The muckrakers were reform-minded journalists in the Progressive Era in the United States (1890s–1920s) who exposed established institutions and leaders as corrupt. They typically had large audiences in popular magazines.
Jazz had its biggest moment in the 1920's so that's out. Speakeasies were very famous because cops were always taking these liquor stores down. And of course, flappers were famous at liquor stores and jazz so i believe football is out ;)