A group of historians are doing research on the causes and effects of the Great Depression in the United States. Each record can be used by a historian who is interested in studying a particular type of cause and effect in the history of that era. Match the records with the correct categories.

Which is the main inference that can be drawn from adam smith's book the wealth of nations? a) for an economy to work flawlessly, it shouldn't have to serve and moral goals. b) the government must control a free-market economy, or economic problems will arise. c) a free-market economy works well only without the government's interference. d) free trade will only hurt economies and should be stopped by governments.