Which themes were prevalent in the works of Theodore Dreiser?

The works of Theodore Dreiser often highlighted the effects of industrialization and capitalism on individuals and society. He is well-known for his naturalistic approach to literature, which examined the complexities of human experience against the backdrop of societal structures. In his notable novels, such as "Sister Carrie" and "An American Tragedy," Dreiser critiques the industrial capitalist system and exposes the harsh realities faced by individuals striving for success and the American Dream.

Dreiser's narratives typically illustrate how societal forces, particularly those associated with wealth and power, can shape and often manipulate the lives of ordinary people. His advocacy for business regulation stems from his belief that the rampant exploitation and moral corruption found within industrial capitalism necessitated oversight to protect the vulnerable. This theme of critiquing the industrial elites and their impact is a defining characteristic of his work, making it the correct answer.