Final answer:
John D. Rockefeller would be described by Folsom as predatory and aggressive, due to his business tactics like horizontal integration and creating trusts, which allowed him to dominate the oil industry.
Step-by-step explanation:
Folsom would most likely call John D. Rockefeller a predatory and aggressive businessman. Rockefeller, known for his work in revolutionizing the US industry through his company, the Standard Oil Company, was a figure of significant controversy. His business practices included horizontal integration and the creation of trusts to dominate the oil industry, which many progressive reformers condemned due to the negative impact on competitors and the consolidation of power.
Rockefeller had a talent for making secret deals and using his strategic position to lower prices and drive competitors out of business, only to raise them again once he had market dominance. His philanthropic efforts did little to soften the image of his ruthless approach to business. The legacy of Rockefeller in industrial America is a complex mix of business acumen, ruthless competitiveness, and transformative impact on corporate structure.