D. more American workers relocating to urban centers.
The factory system was first adopted in Britain at the beginning of the Industrial Revolution in the late 18th century and later spread around the world.[1] It replaced the putting-out system. The main characteristic of the factory system is the use of machinery, originally powered by water or steam and later by electricity. Other characteristics of the system mostly derive from the use of machinery or economies of scale, the centralization of factories, and standardization of interchangeable parts.
