Which of the following statements best reflects the cause for BOTH the fall of the western Roman empire and the fall of Han China?
a. The collapse of imperial power coincided with the demographic impact of epidemic disease and external threats
b. Invasion by fierce northern nomads brought diseases which undermined the existing social order
c. New religious traditions threatened the existing social order
d. An unchecked military and constant threat of invasion
The best option would be that "a. The collapse of imperial power coincided with the demographic impact of epidemic disease and external threats," since external enemies had more power to attack and pillage.
