What federal government organization was used to regulate railroad, telephone, and telegraph companies?

The federal government organization used to regulate railroad, telephone, and telegraph companies was the Interstate Commerce Commission.

Explanation:

The Interstate Commerce Commission was founded by the Interstate Commerce Act, a federal law of February 4, 1887. The ICC was the first independent agency at the federal level. With the approval of the United States Senate, the President of the United States appointed its members who were somewhat independent in their decisions.

The original purpose of the ICC was to regulate rail traffic (and later also truck traffic), such as ensuring fair freight rates or preventing discriminatory pricing. From 1910 to 1934 it also regulated telephone services between the states. This responsibility passed to the newly created Federal Communications Commission in 1934. Due to various deregulation measures by the US Congress in the 1970s and 1980s, the ICC lost more and more of its competencies. It was abolished in 1995. Since then, the responsibilities that have remained to it have been carried out by the Surface Transportation Board.

the answer is states.