Final answer:
Keynesian economics, neoclassical economics, and monetarism are three key economic approaches to policy analysis.
Step-by-step explanation:
There are three key economic approaches to policy analysis: Keynesian economics, neoclassical economics, and monetarism.
Keynesian economics emphasizes the role of government in managing the economy, particularly through fiscal policy. Neoclassical economics focuses on market forces and the efficiency of free markets. Monetarism emphasizes the importance of monetary policy and the control of the money supply.