Which major reform regarding voting was made of a result of the progressive reform movement?

The Progressives fixed some of their reforms into law by adding amendments 16, 17, 18, and 19 to the US Constitution. The 16th amendment made an income tax legal (this required an amendment due to Article One, Section 9 of the Constitution, which required that direct taxes be laid on the States in proportion to their population as determined by the decennial census). The Progressives also made strides in attempts to reduce political corruption through the 17th amendment (direct election of U.S. Senators). The most radical and controversial amendment came during the anti-German craze of World War I that helped the Progressives and others push through their plan for prohibition through the 18th amendment (once the Progressives fell out of power the 21st amendment repealed the 18th in 1933).

Explanation: The ratification of the 19th amendment in 1920, which recognized women's suffrage was the last amendment during the progressive era.[128] Another significant constitutional change that began during the progressive era was the incorporation of the Bill of Rights so that those rights would apply to the states. In 1920, Benjamin Gitlow was convicted under the Espionage Act of 1917 and the case went all the way to the Supreme Court, where the justices decided that the First Amendment applied to the states as well as the federal government. Prior to that time, the Bill of Rights was considered to apply only to the federal government, not the states.