Immediate conflicts:
... The USA had atomic weapons and the USSR did not. (The US would not share that technology with the Soviets.)
... The USSR did not assure that free and fair elections took place in Eastern Europe -- it saw to it that Soviet-aligned governments were installed there.
... Tensions over the East Germany / West Germany and East Berlin / West Berlin division of territory.
Deeper causes:
The USA was committed to capitalism and democratic institutions of government.
The USSR was committed to communism and imposed authoritarian government.
The Cold War was mostly a tension between these worldviews.
The correct answer is:
The landlords.
In the account of the harsh existence that he and his family encountered in the one-room tenements of South Chicago, Richard Wright's "The One-Room Kitchenette" refers to the building landlords as “the bosses of the buildings”, who were keeping black people in specific apartments, without any mobility, and developing racially restrictive housing covenants.
The super continent was named Pangaea.
