Elecciones federales de México de 1955

On October 17, 1953, during the presidency of Adolfo Ruiz Cortines, a constitutional reform granted Mexican women full citizenship and the right to vote in federal elections. Women voted in a federal election for the first time in 1955.

A useful distinction: women had been able to vote in municipal elections since 1947, but 1953 is the year of full national suffrage, which is the date the exam asks for.