Why did leaders in the United States believe that communism posed a threat to democratic nations?

The United States government was initially hostile to the Soviet leaders for taking Russia out of World War I and was opposed to a state ideologically based on communism. However, the Soviet stance on human rights and its invasion of Afghanistan in 1979 created new tensions between the two countries

i believe it is the second one.   if correct plz mark brainliest.

b europeans take corn to africa. corn becomes an important crop there.