Which of these was a result of massive migration to the west in the 1800s

B. Boomtowns. It was very hard for regular everyday people to get jobs that paid above minimum wage back in the day. If you did not have excellent ancestors, then you were not excellent. These 'boomtowns' gave people with bad genetic lines a chance to make a name for themselves and a chance to make enough money to keep food on the table.