The correct answer is C) interstate highways.
What most affected the growth of the suburbs around the Atlanta area was interstate highways.
Atlanta’s metropolitan area is one of the largest in the United States. Indeed is the ninth-largest in the U.S. The construction of new and modern highways affected the growth of the suburbs around the Atlanta area. There are many counties around the city of Atlanta such as Fulton, DeKalb, Lamar, Jasper, Henry, Barrow, and Walton.