Final answer:
The correct answer to the question is c) Some western states allowed women to vote before 1920.
Step-by-step explanation:
Notably, states like Wyoming, Utah, Idaho, and Colorado had granted full voting rights to women by the early 1900s. This progressive shift in women's suffrage was influenced by several factors, including the different social and economic dynamics in the West, which were less bound by the traditional gender roles prevalent at the time.
Understanding the context, women's suffrage in the United States started in the territories with lesser populations, such as Wyoming Territory enfranchising women in 1869. By 1900, several Western states had recognized the right to vote regardless of gender in response to women's movements and as a strategy to attract more women to these regions. The efforts of suffragists, campaigns, and the evolving social ideals of the time led to the incremental enfranchisement of women.
Eventually, by 1919, thirty states and territories had approved women’s suffrage in some form, with half of these allowing women to vote in all elections. This set the stage for the passage and ratification of the 19th Amendment, which was fully ratified by 1920, granting women the right to vote nationwide.