It was becoming a very popular entertainment event.
Babe Ruth
Popular 1920's DanceThe Foxtrot became popular in the 1920s.
the automobile
baseball
Baseball
It was becoming a very popular entertainment event.
Baseball was because it was America's sport in those days
baseball football soccer polo swimming, runnung
Babe Ruth
Realism was a popular artistic genre of the 1920s.
Popular 1920's DanceThe Foxtrot became popular in the 1920s.
Mah Jong, crossword puzzles, football, etc. were popular games in the 1920s.
realism
The Charleston.
A few of the most popular songs in the 1920s was Sonny Boy, See See Rider Blues, and King Porter Stomp. The most popular type of music during the 1920s was jazz.
Baseball must have been one of the two. I can't guess the other.