Normally, I would argue that a textbook or a course syllabus would be best in answering a multiple choice question like this. Yet, I will go out on a limb and argue that A could be the only possible answer. It should be noted that I think it was difficult to find anything that Americans were able to take a real comfort from on that sad day, but A would be the closest one. Rudy Giuliani was the mayor on September 11, so B is eliminated. The apprehension of "the terrorist" was anything but quick. Zaccarias Moussaui's apprehension did not bring any closure because he was not "the terrorist" responsible. In fact, one could argue that the recent killing of Osama Bin Laden a couple of weeks ago would be the closest element to "apprehending" the "terrorist responsible" because the rest of the terrorists died on the planes. President Clinton was not in office at the time, which makes D a non option. I think that A would have to be the most logical choice of the four.