Americans initially supported the French Revolution because it was the revolt of the common people against an absolute monarchy, which Americans related to. Option A is correct. It was inspired by the idea of republican rule.
The French Revolution marked a period of widespread social and political upheaval in France and its colonies in 1789. The Revolution overthrew the monarchy, established a republic, involved violent periods of political turmoil, and finally gave rise to a dictatorship under Napoleon who established many of its principles to places he conquered in Western Europe and beyond.