The answer to your question is A, most likely.
The answer is to this is D.) The Great Dividing Range.
Hope it helps!
Answer:
Agriculture allowed people to stay in one place, and increased food production caused the population density to expand far beyond levels that could be sustained by hunting and gathering alone. This growth in population density provided a critical mass of people to sustain and spread contagious infectious diseases.
1739 by Jean Baptiste Charles Bouvet De Lozier
