Which region is characterized by red clay and gently sloping hills and is the most highly populated region in Georgia, containing most of the state’s major cities, including Atlanta? A. Ridge and Valley B. Coastal Plain C. Blue Ridge D. Piedmont

D. Piedmont

The region characterized by red clay and gently sloping hills, and is the most highly populated region in Georgia, containing most of the state's major cities, including Atlanta, is the D. Piedmont region.

The correct answer is D. Piedmont.

To arrive at this answer, we need to understand the various regions of Georgia and their characteristics. Here's a brief explanation of each region:

A. Ridge and Valley: This region is located in the northwest part of Georgia and is characterized by long parallel ridges and valleys. It's not the region we are looking for.

B. Coastal Plain: This region is located in the southern part of Georgia and is characterized by flat or gently sloping terrain, coastal marshes, and barrier islands. While it is geographically closer to the description of red clay and gently sloping hills, it is not the most highly populated region in Georgia.

C. Blue Ridge: This region is located in the northeast part of Georgia and is known for its rugged mountains, including the highest peak in Georgia, Brasstown Bald. It is not the most highly populated region.

D. Piedmont: This region, located in the central part of Georgia, is characterized by red clay soil and gently sloping hills. It contains most of the state's major cities, including Atlanta, making it the most highly populated region.

Therefore, the answer is D. Piedmont.