Which of the following contributed to the decline of the Roman Republic?

The decline of the Roman Republic can largely be attributed to repeated civil wars, which created significant instability within the state. These internal conflicts arose from power struggles among political leaders and various factions, leading to a series of violent confrontations that weakened the governmental structure and its ability to function effectively. The civil wars not only drained resources but also diverted attention from external threats and governance tasks, exacerbating the turmoil.

While other factors like foreign expansion and economic aspects could have influenced the Republic, they did not have the same direct, destructive impact as the civil wars. Expansion, for instance, often brought wealth and resources rather than directly contributing to decline, and the alliances with neighboring states usually aimed to create stability rather than exacerbate conflict. In contrast, the environment created by ongoing civil wars destabilized the Republic so profoundly that it ultimately led to its fall.