Answer:
The correct answer would be option D, All of the above.
Step-by-step explanation:
If you want to think like an economist, then you must have the knowledge about the theories based on economies, the relationships between the theories, the concepts in the theories, the case studies about the economies to have a real time knowledge about them. Also you need to listen to the economic news to stay up to date about the current economic structures and situations and to link the news with the concepts and theories that you studied and with the case studies. This type of interlinking of the economic events and theories and case studies would help you greatly in thinking like an economist.