Final answer:
During the 1800s, Atlanta experienced a steady increase in population, in line with the trends of rapid urban population growth and overall exponential human population growth during that era.
Step-by-step explanation:
The population growth in Atlanta during the 1800s was characterized by a steady increase. This was consistent with the broader trend in the United States where the late 1800s saw rapid population growth, particularly in urban areas. Major cities faced both challenges and opportunities due to this growth, as the population dynamics shifted from rural to more urban concentrations. The human population on a larger scale experienced exponential growth during this period owing to a significant drop in death rates, especially seen in 18th- and 19th-century Europe. While birth rates remained high initially, they eventually began to fall, leading to a slowdown in population growth. Therefore, based on the options provided, the correct answer would be B) Steady increase.