Final answer:
The fall of the Roman Republic was primarily caused by economic inequality, political corruption, and social unrest, which are important lessons for modern republics facing similar issues.
Step-by-step explanation:
The primary causes for the Roman Revolution, or the fall of the Roman Republic, revolved around economic inequality, political corruption, and the social unrest stemming from a rising proletariat class displaced by war and changes in the Roman economy.
As the Republic expanded, it faced increasing internal strife due to the concentration of wealth in the hands of a few, a corrupt political system where politicians sought the support of the masses through handouts and entertainment, and a growing threat from powerful military leaders who would eventually lead Rome into civil war and the establishment of the Roman Empire.
The fall of the Roman Republic demonstrates how a combination of economic distress, political instability, and ambitious leaders can converge to unravel the fabric of a state. It is a cautionary tale for modern republics which also grapple with economic disparities, trust in political processes, and the role of powerful individuals in shaping the future of the nation.
Therefore answer is a) Economic inequality, Political corruption, Military decline.