Teams that are empowered to take responsibility for acting autonomously on identifiable pieces of work are referred to as:
a. informal groups.
b. interest groups.
c. self-managed work teams sequential task interdependence groups.

self-managed work teams

Explanation:

A self-managed work team is one in which group of employees are independently responsible and accountable for the task and project completion. They are not supervised by any leader. All the activities related task like planning, schedule management, monitoring the progress of work are all managed managed within the team.  

The advantage of such team is that it  

•Increases sense of ownership among members.  

•Better decision making because decision is inclusive and expertise of each member is involved in it

•Increases sense of unity as team member support each other in task and if one takes leaves other member takes care of it.

•It is comparatively less costly as well as management of team is also handled by the team member and does not require any additional supervision

Since problem says that teams are empowered to take responsibility autonomously for their work. It is characteristic of self managed work teams as discussed above.

answercommunism;