D is the correct answer. This is because during the 1800s religion was no longer a major deciding factor. Money was the biggest drive.
It's not A because farms were small and if you couldn't support your family at that area any longer you had to move to a place where you could.
It's not B because finances and depression were starting to get large. (I don't have a great explanation as to why for this one other than money.)
It's not C because the government and monarchs were also running put of money, so they taxed the people. When taxes got way to high people had to move or go into debt.
It's not E because this was at the tail end of the industrial revolution. More work= more money.
Hope this helps :)
