D. They were encouraged to support the patriot effort.
The French had been covertly aiding the American colonists since the beginning of the Revolutionary War, but the decisive victory at Saratoga in 1777 was a turning point. It convinced the French government that the Americans had a chance of winning their independence from Great Britain. As a result, they decided to formally enter the war on the side of the Americans. In February 1778, France and the United States signed the Treaty of Alliance, establishing a military partnership against Britain. This led to significant French military and financial support that was crucial to the ultimate success of the American Revolution.