Why did most immigrants move to the cities in america

Many Europeans who decided to emigrate to the American colonies first landed in New York City, Boston and Philadelphia. During the late colonial period in America there were jobs in textile mills and other manufacturing facilities that were in or near to the larger cities. 
here were also craft product shops where Europeans could work or if they came with enough money they could open shops in or near cities. The cities were also home to the publishing industry.

For a better live, farm land, or because America is the land of oppertunity

Ibelieve that the answer is (a).