Answer and Explanation:
The two most likely effects of the decline in the Roman Empire, especially on significant level are:
1. The decline of the Roman Empire caused much trading to be interrupted because merchants experienced invasions from enemies and barbarians who wreaked havoc and instilled fear in traders, thus greatly interrupting trading and destroying financial and economic centers.
2. The decline of the Roman Empire lead to the eventual downfall of many cities, great and small: the attacks from outside, and the corruption and fighting from within (inside), made many citizens to lose interest and abandon great cities and well-known centers of trade which rapidly deteriorated.
