Final answer:
The AFL-CIO is the dominant labor interest group in the United States, comprising various unions such as the United Auto Workers and the International Brotherhood of Electrical Workers.
Step-by-step explanation:
The dominant labor interest group is the AFL-CIO, which stands for American Federation of Laborers/Congress of Industrial Organizations. The AFL-CIO is the largest labor union in the United States. It is a federation of many different unions, including the United Auto Workers, the International Brotherhood of Electrical Workers, and many others.