Answer:
Answer is option D i.e. They maintained control of production and distribution of their products.
Explanation:
In the late nineteenth century, the main reason for the growth of the business was the inclusion of vertical and horizontal integration in the manufacturing and selling processes. In the process of vertical integration, the company tends to integrate two or more manufacturing processes to minimize cost, and increase efficiency. In the late nineteenth, the production and distribution processes were strategically integrated which contributed as means of growth. This integration was referred to as vertical integration.