The following responses contributed to the beginning of the decline of the Roman Empire:
- The soldiers hired on the frontiers were not willing to go defend other parts of the empire.
- Soldiers in the outer parts of the Roman Empire often supported local commanders instead of the emperor.
- Regardless of the strength of the emperors, the Roman army was unable to hold back barbarian invasions from the south and west.
- Incompetent rulers placed huge tax burdens on the Roman citizens.
All four statements are valid factors that contributed to the decline of the Roman Empire.