The correct answer is B) era of the 1930s.
The era of the 1930s was NOT one of the 4 eras of immigration to the US.
Most historians agree on the idea that there were four eras of immigration to the United States. These were the colonial American times, where English colonists started to found the firsts English colonies in North America like Jamestown, Virginia or Cape Cod, Massachusetts. Then, the second era, 1790 to 1820. The third era, 1820-1930, and finally the period after 1965.