I believe the answer is Religion
In the early history of the U.S., some states allowed only white male adult property owners to vote, while others either did not specify race, or specifically protected the rights of men of any race to vote. Freed slaves could vote in four states. Women were largely prohibited from voting, as were men without property.
Pretty sure your answer is B. They didn't get equal rights until the 60's, I don't believe they were removed from jobs, and I'm fairly certain they wouldn't have done work without pay (The Great Migration is a good example of that).
B. Constitution
...is the answer to your question :)
