The correct answer is Robber Baron.
Robber Baron was a common title given to business owners who practiced unfair or anti-competitive businesses practices during the Gilded Age (late 1800's- early 1900's). Individuals like John D. Rockefeller, Andrew Carneige, and JP Morgan tried to completely eliminate their competition in their respective industries. For example, Rockefeller almost had a monopoly on the oil/kerosene industry while Careniege was known for his steel production.