How did Rome went from an Empire to a Republic? Explain pls

The Roman Republic
Rome was once a city-state, ruled by kings. Beginning in 509 BCE, a new form of government took shape—the Republic.
During the early years of the Republic, power was in the hands of the patricians, a privileged class of Roman citizens. The patricians had control over all religious offices and issued final approval of decisions made by the Roman assemblies.
However, debts and an unfair distribution of public land upset the poorer Roman citizens, known as the plebeians. So, they decided to withdraw from the city-state and form their own assembly, and elect their own officers. Their main goals were debt relief and a more fair distribution of newly conquered territory.
By 287 BCE, wealthy plebeians achieved political equality with the patricians and a new power-sharing, ruling class was born.

The correct answer is c