<span>C. He was working to reduce U.S. economic influence in Cuba.
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Changes in color or contour lines...be sure to check online :))
You did not state a specific time period about which you're interested. However, in general the war-weary Americans were concerned with any event in Europe that seemed to destabilize the whole region. They were concerned with events like these because they had the potential to seriously influence the peace in America, not only in Europe.
Until about 20 years ago, most scholars of Mongol-era China emphasized the destructive influence of Mongol rule. One major scholar of Chinese history even wrote: "The Mongols brought violence and destruction to all aspects of China's civilization. ... The Mongols perceived China as just one section of their vast empire.