Answer:
C. By appealing to the emotions of the audience
Step-by-step explanation:
In the phrase "Because if we forget, we are guilty, we are accomplices." the author is associating the speech with the emotion. The author wishes to appeal to the emotional side of the public, so that people are aware and moved by the horrors of World War II. Thus, the author tries to persuade the public saying that nobody should forget the atrocities caused by the war, because those who forget will be an accomplice and blame.