I am not much sure but generally there are 2 types of economic theories:

Microeconomics:
1-Market Structures (Monopoly, Competition, Supply, Demand, Price, Equilibrium Analysis)
2-Production Theories (Fixed Cost, Opportunity Cost, Variable Cost, Mass scale economy, Production Possibility Frontier, Scarcity, Comparative Advantage, Small scale vs large scale production, Absolute advantage, Capital cost)
3- Game theory (uncertainty, imperfect information, Information asymmetry, moral hazard, laws of contract, principle agent theory)- Pretty advanced this topic is, might not come
4- Market failure, government failure, externalities..

Macroeconomics
1- Growth, GDP, GNI, National Income, Savings main concepts
2- Business cycle: Circular flow of income, Aggregate supply, Aggregate demand and Unemployment
3-Inflation and Monetary Policy
4- Fiscal Policy
5- Public finance, welfare choices etc.


Note: These are more or less what we studied in our Economics classes in BBA Honors and then I did a course in development economics as well. I extracted this index from Wikipedia, but it appears quite comprehensive. Do not know to which depth does NTS want to go in their test.

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Umair Ali
Wah Cantt Pakistan