Answer:
D because the 1800's were a time that machines were being properly utilized so that products could be made much faster than in the late 1700's.
Step-by-step explanation:
The 1800's was apart of the age of industrialization were lots of industry grew because of innovations such as the train. The Industrial Revolution took place in between 1820 and 1840. This transition included going from hand production methods to machines, new chemical manufacturing and iron production processes, the increasing use of steam power and water power, the development of machine tools and the rise of the mechanized factory system.