The answer is B. Also known as double jeopardy.
The Monroe Doctrine demonstrates American Nationalism because the United States lays claims to all of the land in the American Continents that is not already conquered. President Monroe was a great advocate of nationalism and reached out to all the regions of the country. In foreign policy, he put the nation on an independent course, no longer tied to the mast of European policy.
If it makes sense in context, the 1973 oil crisis could be a suitable answer.
