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

The Fifteenth Amendment prohibited denying the vote based on race, extending voting rights to formerly enslaved men and other Black men. It did not grant women the right to vote, which led to disagreements within the suffrage movement and the formation of two major organizations. Thus, the correct choice is “it granted formerly enslaved men the right to vote, while women were still denied this right.”

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