What is the main purpose of the talk？A．To show what happens after an economy has experienc

What is the main purpose of the talk？

A．To show what happens after an economy has experienced a boom-and-bust cycle

B．To illustrate the conditions needed to produce a boom-and-bust cycle

C．To demonstrate how boom-and-bust cycles have changed over time

D．To explain why the boom-and-bust cycle is not a frequent historical occurrence

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