Final answer:
Robber barons during the industrial revolution often kept workers' wages very low due to lack of competition and surplus of labor. They could control labor terms including wages and working conditions.
Step-by-step explanation:
In the era of industrialization, robber barons often had monopolistic control over industries. Because they had no competition, they dictated terms of labor, including wages and working conditions. From the given options, it can be said that robber barons B: kept workers' wages very low. This was possible because of the lack of competition and the surplus of labor. Workers had little choice but to accept whatever wages were offered.
Regarding other options, A is misleading as prices of goods can be very high in monopoly situations due to the lack of competition. C is incorrect, as monopolies and poor labor conditions were often associated. D is also incorrect as child labor was commonly used during the industrial revolution, in part by such monopolistic entities.
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