Which of the following statements best describes migration in the 20th century?
a. large numbers of people moved to foreign colonies during the 20th century.
b. migration during the 20th century was purely for economic opportunity.
c. migration during the 20th century was influenced by several factors, including war and politics, urbanization, and economic opportunities.
d. migration in the 20th century was influenced by european imperialism

The correct answer is "C": Migration during the 20th century was influenced by several factors, including war and politics, urbanization, and economic opportunities.

During the 20th century, many immigrants came to the US not only for economic opportunities but also for the rapid growth of industrialization and urbanization. More than 20 million immigrants came from Central, Eastern and Southern Europe. Besides, Jews from Eastern Europe arrived in large numbers fleeing religious persecution. After the Second World War, Congress passed special legislation allowing refugees from Europe and the Soviet Union to enter the United States. The US provided immigrants with job opportunities due to the process of industrialization which also led to an increasing urbanization in the big cities.

the answer is a. laws were enacted in the aftermath of the plot to make it harder to free slaves,increasing sectionalism