Answer:
D
Step-by-step explanation:
After the second world was was over up to the early part of the 1970s, the United States experienced a great period of economic expansion, one of the greatest in the history of the world. This led to an increase in the Gross Domestic Product and productivity from the "middle class" citizens level. Also due to the abrupt expansion of locals to the West, high birth rate and population growth occurred in this period. However, there was no case of any cultural consensus during this period.