The correct answer is C. 1792 AD.
France became a republic in 1792, after the French Revolution. The revolution began in 1789 with the storming of the Bastille, a prison in Paris. The revolutionaries were angry about the high taxes and the lack of representation for the common people. They wanted to create a new government that would be more fair and just.
The revolution was successful in overthrowing the monarchy and establishing a republic. However, it was also a very bloody and violent time. Millions of people were killed or injured. The revolution ended in 1799 with the rise of Napoleon Bonaparte.
Option A is incorrect because it is the year that the French Revolution began. Option B is incorrect because it is the year that the French Revolution ended. Option D is incorrect because it is too early.