After two assembly line employees have a loud argument in the cafeteria, the foreman calls them into his office to resolve the conflict. which basic managerial role does this best describe?

This is the role of a disturbance handler. When the foreman takes the initiative to find out what is going wrong and tries to figure out a way to smooth everything over without causing too much of an issue for the business, he is taking such a role. This allows the business to function while still getting grievances aired out.