人类社会的基本经济问题 (三)解决人类社会基本经济问题的影响因素 其 Economic System 其 Scarcity #t Choice and opportunity cost Opportunity cost of any activity is the sacrifice made to do it. It is the best thing that could have been done as an alternativeEconomic System Scarcity Choice and opportunity cost Opportunity cost of any activity is the sacrifice made to do it. It is the best thing that could have been done as an alternative. （三）解决人类社会基本经济问题的影响因素 三、人类社会的基本经济问题