(D) The desire to contain communism in developing parts of the world.
Explanation:
To start, you have to know a thing or two about wars with the US. JFK was president during the Cuban Missile Crisis, he attempted to repel communism and had mild success. Then after that came Lyndon B Johnson aka LBJ, he tried to repel communism in Vietnam, and had mild success as well. Then Nixon came after and ended the Vietnam war but the Cold War was still happening, which was against communism aka USSR. Then there's Gerald Ford, I have no idea what he did but he probably continued the trend of being against communism.
TLDR
It reflects the US against communism during the 20th century.
