The correct option is D
Towards the end of the 19th century and the beginning of the 20th century, the United States managed to round off the territory from the small Atlantic strip to the peaceful façade, by conquering the immense territories of the Southwest. Before the formidable pressure, fomented by the federal government and turned into an epic that immortalized the Hollywood industry with the legendary Far-West, of farmers, planters, merchants, adventurers, European immigrants and missionaries, the mythical "Frontera", considered the territory Savage par excellence, it became a powerful factor in the expansion of capitalism. However, the conquest of the West served not only to increase agricultural, livestock and mining space (gold rush in California), and to promote the demographic development, but also to forge the myths from which the new nation has been nurtured until today. American
In this process, industrial production went from less than 2,000 million dollars per year to more than 13,000, in the same way the number of employees in industry, mining, construction and services went from less than 4 million people up to 18 million. The factors that determined industrialization were the abundance of natural resources, the growth of the population, the accumulation of capital and foreign investment, immigration also provided a broad and cheap labor force. During this period, the consolidation of companies into large-scale units became evident. This consolidation was based largely on the birth of the trust that were agreements of the shareholders of different companies of a certain economic sector to unify the direction and management of the same and reducing competition.
