<span>D)	they used rivers and bodies of water for food and for trade.</span>
        
                    
             
        
        
        
During the 1950's, the US had adopted a policy of containment. The goal was to stop the spread of communism on a global scale. This included giving financial and military aid to countries who might fall into the hands of a communist government. A perfect example of this would be South Korea. 
During the early 1950's, North Korea (a communist country) invaded South Korea. America, worried about the spread of communism, wanted to ensure that South Korea stayed free of this communist system. To do this, the US helped convince the United Nations to intervene in the conflict between North and South Korea. 
        
             
        
        
        
Answer:
Answer letter (D)
Explanation: 
The Consumer Price Index (CPI) is a tool that examines the average of prices of a basket of consumers goods and services.
The CPI is used as an economic indicator and is used as a measure of inflation and effectiveness of the government’s economic policies.