Which factor contributed to the collapse of both the roman empire and the han dynasty?

a. overfarming and urbanization depleted the natural resources of both regions.

b. populations in both regions declined from illnesses that spread quickly.

c. wars with invaders from neighboring lands weakened both empires.

d. lack of technological advancements left both cultures lagging

The correct answer is C) wars with invaders from neighboring lands weakened both empires.

The factor that contributed to the collapse of both the Roman Empire and the Han Dynasty is that wars with invaders from neighboring lands weakened both empires.

The Han Dynasty declined due to internal political disputes among people in power and rebellion form peasants that were tired of heavy taxation. The Roman Empire declined due to divisions and political differences among the elite and the extensión of its large territory made difficult to control. That is why the factor that contributed to the collapse of both the Roman Empire and the Han Dynasty is that wars with invaders from neighboring lands weakened both empires.  

a, he promoted disarmament