Question

progressive reforms that sought to break up monopolies and limit their power were known as
free enterprise.
trust - busting.
unionism.
restrictive legislation.

Explanation:

• Free enterprise: Refers to an economic system where businesses operate with minimal government interference, not about breaking up monopolies.
• Trust - busting: This term specifically refers to the efforts (often by the government) to break up large monopolistic trusts (which were powerful business combinations in the past).
• Unionism: Relates to the formation and activities of labor unions, which are about workers' rights and collective bargaining, not monopolies.
• Restrictive legislation: Is a very general term. While some laws to break up monopolies could be called restrictive (in the sense of restricting monopolistic behavior), "trust - busting" is a more specific and well - known term for this action.

Answer:

B. trust - busting