Final answer:
Business reforms in the late 19th and early 20th centuries were a reaction to the monopolistic practices of robber barons. These reforms led to more active government involvement and regulation, such as the Sherman Anti-Trust Act, to prevent monopolies and protect the public interest. The correct option is A.
Step-by-step explanation:
Reforms in business during the late 19th and early 20th centuries were primarily a reaction to robber barons, powerful industrialists and financiers who amassed vast fortunes through monopolistic practices and exploitation. These business magnates were often seen as using unfair business practices to eliminate competition and control various industries.
In response to public outcry against these monopolistic practices, the government began to implement regulatory measures such as the Sherman Anti-Trust Act to ensure fair competition and prevent the formation of monopolies.
Over time, reformers pushed for more active government involvement in regulating the economy. This need for oversight was due in part to the lack of success of previous regulations in significantly curtailing corporate growth or improving working conditions. Consequently, legislation and regulatory agencies evolved into more effective tools to limit corporate power and protect the public interest.