Which of the following best states the theme of "Chicago"?

A. People love their birthplaces, no matter how brutal and poverty stricken those places may be.
B. When cities get too big, they dwarf the lives of the people who live in them.
C. In its early days, Chicago had more variety and activity than any other American city.
D. Like people, cities grow up with their own personalities and have both good and bad traits.