I beleive the answer would be B: Buring fuel
The Paris Peace talks began in May 1968 and concluded on January 27, 1973.
The negotiations started with the International Control Commission and was changed to International Commission of Control and Supervision to complete the accord. The Paris Peace Accords was a peace treaty titled Agreement on Ending War and Restoring Peace in Vietnam and signed by the United States, South Vietnam, Viet Cong and North Vietnam.
After the end of World War II, Soviet forces occupied the country, seeking dominance of their Socialist Ideology, and there they stayed throughout the Cold War.
Occupying it was how they managed to take control of this portion of the country. Their ideological war against the United States' Capitalism was how they managed to maintain control of the area.
During this period the Berlin Wall was built, and it marked the division between Western and Eastern Germany.