Why does international trade require a system for exchanging currency? a. countries involved in trade may have different currencies. b. there are countries in the world that will not do business with each other. c. some countries try to limit the number of imports by not taking certain currencies. d. each nation believes its currency is the best and doesn’t want to use other nations’ currencies.

The answer would be A. Process of elimination indicates that answer B is wrong because if they do not do business with other countries then they are not in the trade system. Answer C is incorrect because it involves countries not taking currency from other countries which contradicts the purpose of an international currency exchange system. Finally, letter D is incorrect because while it makes sense, it is arrogant and completely irrelevant since they can not use other countries currency in their home country anyway due to the different values.