Which factor promoted the development of new forms of entertainment such as dance halls, carnival rides, and professional sports?

ABusy city people no longer had time for older, more time-consuming forms of entertainment.
BThe new middle class had leisure time and extra money.
CNew technologies allowed people all over the world to view entertainment everywhere.
DUnemployed urban workers needed ways to spend their time, so they would not turn to crime.

Verified Answer :

One factor that promoted the development of new forms of entertainment such as dance halls, carnival rides, and professional sports was that "b. The new middle class had leisure time and extra money," since the US economy was in a "boom" period. 

The correct answer is B. The new middle class had leisure  time and extra money.

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