English No links! I will report them

What is the best way to organize the sentences to express how the author develops a central idea in the passage?
Put them in order
A)
The author describes how people came from England,
Ireland, the German and Russian empires, and
Scandinavian countries to escape famine, political
and economic oppression, or in search for greater
opportunities in America."

B) This detail shapes the idea because it lists European
countries that the people came from and
explains several reasons why they left for America.

C) A central idea in the text is that many of the people
migrating to America were European immigrants.