Final answer:
The French Revolution, which started in 1789, led to the end of the monarchy in France with the execution of King Louis XVI during the Reign of Terror, and established a republic (a).
Step-by-step explanation:
The people of France ended the monarchy through the French Revolution, which began in 1789. This revolution was a direct challenge to the absolute monarchy that had ruled France for centuries. It involved a series of events that eventually led to the overthrow of King Louis XVI. One of the most significant events was the Reign of Terror, which began with the execution of King Louis XVI in 1793 and included a campaign of severe violence against those deemed enemies of the revolution.
The revolution culminated in the creation of a republic and the radical restructuring of French society, law, and government – a complete departure from monarchic rule. Although there was a brief restoration of the monarchy after the fall of Napoleon, the monarchy could not return to its pre-revolution absolute power due to the constitutional changes implemented as a result of the French Revolution.