What long-term economic factors led to the collapse of the roman empire?
a. trade opportunities went down, and the middle class rose significantly.
b. trade opportunities went up, and the middle class shrunk significantly.
c. taxes went down, and the gap between the rich and poor decreased.
d. taxes went up, and the gap between the rich and poor increased.

D.Taxes went up, and the gap between the rich and poor increased.

Explanation:

Before the Roman Empire collapsed, it was a large empire that encompassed large portions of land in Europe, the Middle East, and North Africa. In order to keep its power in all of its vast territories, the Roman Empire depended greatly on its large army. Therefore, in its final phase, the empire had an increasing territory and an increasing army needful of resources. For this reason, the Emperor elevated the taxes to collect more money for the troops. This measure increased the gap between the rich and the poor, causing a big economic crisis. This situation was no longer sustainable: social conflicts appeared within the empire and the troops hadn't enough resources to fight against the barbarian hordes. Finally, the Roman Empire collapsed due to its own weight.

no, to many things have came in to factor