Final answer:
Iron triangles are an aspect of special interest group politics in the United States, benefiting special interest groups by allowing them to influence legislation and policies.
Step-by-step explanation:
Iron triangles are an aspect of special interest group politics in the United States. They involve a symbiotic relationship among congressional committees, executive agencies, and interest groups. These triangles benefit special interest groups, as they provide a means for them to influence legislation and policies in their favor.