Which development was most likely the cause of the other three?
1. growth of urban centers.
2. growth of industrialization.
3. increase in the middle class.
4. increase in agricultural production

2. growth of industrialization    this led to people moving to cities, where the factories were growing. It also led to more people being successful, therefore boosting them into the middle class. Finally, the technology bettered in this time allowed for more agricultural production    :)