Which statement best summarizes the United States policy in Latin
America in the 20th century? *
A. The "Big Stick" policy was repealed.
B. The main goals of the US has been to bring about the unification of Latin American nations
C. The United States has actively supported European involvement in Latin American affairs.
D. The US has intervened in Latin American Affairs when US self-interest has been involved

D. The US has intervened in Latin American Affairs when US self-interest has been involved

Explanation:

In the 20th century, US policy towards Latin America shifted from the Monroe doctrine that demanded that European powers not attempt to colonize any more Latin American states to a policy that demanded that US interests be protected in Latin America. Under President T. Roosevelt, the US decided that they would expand it's commercial interests into Latin America to enable it to control and protect the continent further as well as to assert it's will.

For instance, when in 1903, Columbia refused to grant US permission to build the Pans Canal, the US reacted by supporting Panamanian rebels through back channels and preventing Columbia from retaking Panama when the latter declared independence. The Panamanian government then responded in gratitude by allowing a canal to be built.

Another instance was the Mexican Revolutions occuring from 1910 to 1920 where the US would support any new Mexican government so long as they abided by US foreign policy.

christopher columbus (1492–1504)

it was certainly a debatable decision, mainly because it was based primarily on political - and not on legal or social - views. since the congress at that time was led by members of the republican party, and the territory that the tribes wanted to turn into an exclusively indian state was predominantly democratic, the proposal (as expressed in the constitution) did not succeed, but the constitution itself proved to be of crucial importance in the creation of the state of oklahoma, and, most importantly, it guaranteed the involvement of representatives of the indian tribes in the government of the future joint state.  

as a member of congress, i would have voted to ratify the constitution, or at least to have it tabled. ignoring it was an interested and partial decision.