Concept:Monopoly services that are essential to citizens are best provided by the state or government.
Explanation:Public enterprises are business organizations wholly or partly owned and controlled by the state.
They are established to provide essential services that the government decides should be run as a state monopoly.
Such services include water, electricity, and postal services.
Private, limited liability, or public companies are profit-driven and may not guarantee fair or universal access to these essential services.
Therefore, government ownership ensures the services are provided in the public interest.
Answer:D. public enterprises