The answer for this question is C. The Domino Theory. This theory states that if a country came under communist rule, its neighboring countries and regions would follow as well. This theory is what the US used as a reason to intervene in the different affairs of various countries to stop or prevent communism from spreading.
Miranda incriminated himself without knowing that he could refuse. I hope this helps. ;-)
OC All rock layers are older than the earth
Military draft and vote. Controversial as women still left out
I'm not sure what class this is for, but in Psychology this would be considered Naturalistic Observation. Hope this helps :)