Road systems had to be expanded. Cities had to be built farther apart. Houses inside cities had to be built farther apart. Vehicle choices available to consumers had to be expanded.
I gave my students this multiple choice question: The large-scale development of personal automobiles started in the early 1900s. Which of the following was a major cost associated with the efficient use of these automobiles?

Only one answer is correct among these 4 choices:
- Road systems had to be expanded.
- Cities had to be built farther apart.
- Houses inside cities had to be built farther apart.
- Vehicle choices available to consumers had to be expanded.

Could you tell me which one is correct?

Road systems had to be expanded.