Answer:
D. Mass production
Explanation:
Henry Ford came up with the first assembly line for the production of cars. It was his aim to be able to produce enough cars to meet the high demands. With the assembly line, he was able to produce automobiles more efficiently, lessening the time substantially, to produce a single automobile.
This allowed them to not only produce more automobiles, but also allowed him to maintain the low cost of the car. Being able to produce more automobiles also enabled him to increase his worker's wages.
