I believe that the most appropriate choice is A.
Could you provide more context for the sentence or is that all there is?
The tone of the initial line of dialogue until "Gettysburg" is reassuring, and it utilizes punctuation as a clue. The tone best suited for reading the word "bang" is excited.
The correct choice is C: In the 1950s, most women (60 percent) were content to leave school and remain at home. This statistic might surprise contemporary readers who assume gender equality and expect a majority of women to pursue careers outside of the household.