The passage of the Fifteenth Amendment in 1869 prompted the formation of two major suffrage organizations because

The Fifteenth Amendment prohibited denying men the right to vote because of race, extending voting rights to formerly enslaved men. It did not extend those rights to women, which led to disagreement among suffrage activists and the formation of two major organizations. Therefore, the correct choice is “it granted formerly enslaved men the right to vote, while women were still denied this right.”

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