Mongols were an ethnic group
French Revolution
American Revolution
B is not an example of economic freedom because wages and prices are being controlled by the gov. controlling money is not freedom economically because the individuals are not controlling it themselves (which would be freedom) . The rest of the options are examples of economic freedom.
I would say b. precious stones Example of commodities that have been used as mediums of exchange include gold, silver, copper, salt, peppercorns, tea, large stones (such as Rai stones), decorated belts, shells, alcohol, cigarettes, cannabis, candy, cocoa beans, cowries and barley.