Which theorists argue that the dominant ideology maintains the privileges of certain social groups who act in their own self-interest to keep others in subservient positions?

The answer would be Conflict Theorists. Since conflict theory is a theory set forth by Karl Marx that allege that society is in a state of constant conflict for the reason that of competition for limited resources. It holds that social instruction that is uphold by domination and power, as a substitute than consensus and conformity.