The Vietnam War usually has a negative legacy in the eyes of American citizens. This war caused the lives of thousands of US soldiers and involved hundreds of millions of dollars spent by the federal government. Many citizens did not agree with/understand why we were putting so many resources into a country that was thousands of miles away. This resulted in hundreds of protests across the US.
Along with the "waste" of resource/soldiers, citizens also disliked the way in which the US government used tactics that resulted in the deaths of innocent civilians. The use of Agent Orange was a perfect example, as this herbicide had detrimental health effects on thousands of innocent Vietnamese citizens.
The Apollo Program
(1963-1972)
C is the best answer because it has reason in it and that is what the enlightenment was mostly about