The correct answer is C) "Abolition violated states' rights to choose what their laws should be."
In the U.S., there are federal laws (that affect all states) and state laws that are implemented by the state and only affect that particular state. When Abolition was passed, the states argued that it restricted their freedom to create laws. Southern states supported slavery, and they felt that abolition (federal law) violated the states' rights to implement their own laws.
I would go with B, "populations declined in urban areas"
Explanation:
For all 3, the urban population is much greater in 100 CE than 1000 CE. I find the graphs to be set up in a poor way and you'd expect them to have grown, so forgive me if I'm wrong.
