I think the answer is B I am sorry if I am wrong
Answer: D
Explanation: Without something being written down as a law to follow through with people could do whatever they wanted. But Lincoln was smart and he pushed for the 13th amendment so that everyone in the United States was forced to oblige.
The correct answer is D. Expansion of the Highway system
The urban sprawl was basically people moving form bigger cities into suburbs. This was possible because they had great highways and cars and could easily go to the big city if they needed something, while they could have their peace and quiet in the smaller areas.