Respuesta :
Answer: B. to persuade readers of the seriousness of the American Civil War.
Explanation: In the given excerpt from "The Dark Game: True Spy Stories from Invisible Ink to CIA Moles" we can see the comparison between the number of soldiers deaths in the American Civil War, and in all the other wars from the Revolution through the Vietnam War. The author's purpose for including this detail is to persuade readers of the seriousness and the consequences of the American Civil War