Final answer:
The Sherman Antitrust Act of 1890 is the legislation that addressed the issue of monopolies where one business could dominate the market. This act was intended to combat anti-competitive practices and foster a more competitive economic environment.
Step-by-step explanation:
Anti-Monopoly Legislation
The act that included a monopoly where one business is allowed to dominate the market is the Sherman Antitrust Act of 1890. This act was passed in response to the anti-competitive practices seen in various industries such as the railroad industry, steel production, and oil and gas exploration and refining. The Sherman Antitrust Act made it illegal to monopolize or attempt to monopolize, and also prohibited conspiracies in restraining trade, thereby breaking up monopolies and promoting fair competition.
Monopolies can arise in a variety of ways, including when a single firm controls all or nearly all of the supply of a good or service. These firms can gain significant market power, allowing them to set higher prices and obtain higher profits, often to the detriment of consumers and the economy. The federal government intervened to regulate these monopolies, fostering a competitive marketplace that benefitted both consumers and other businesses.
The definition of a 'market' can be complex, as exemplified by the case of DuPont, which argued successfully that it did not have a monopoly on cellophane since it competed in the broader market of flexible packaging materials. Similarly, legal monopolies are sometimes permitted for utilities where economies of scale make a single provider more efficient, subject to government regulation to protect consumers.