The major reason that government control or regulation of railroads and large production entities because of monopolies. In the late 19th and early 20th centuries there was major growth in industries such as the railroad and oil industries in the United States, at this time companies became monopolies in these industries and thus there was pressure on the U.S. Government to weaken the control of these monopolies.
The primary reasons for wanting government control of railroads and large businesses included the economic gap between the wealthy and the poor, low wages, and the existence of monopolies. These issues led to increased public demand for regulation to ensure fairness and competition in the market. Therefore, the answer is D. All of the above.
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