Concept:Communism is defined by centralized control and the absence of political pluralism.
Explanation:Under communism, the state usually controls both political and economic life.
Power is concentrated in a single party or a small leadership group.
This limits opposition and political freedoms, which often leads to dictatorship.
Free enterprise, liberal democracy, and a multi-party system contradict communist principles.
Thus, the characteristic feature among the options is dictatorship.
Answer:C. dictatorship