Read the excerpt from John F. Kennedy's first inaugural address. Then, answer the question that follows.

"Finally, to those nations who would make themselves our adversary, we offer not a pledge but a request: that both sides begin anew the quest for peace, before the dark powers of destruction unleashed by science engulf all humanity in planned or accidental self-destruction..."

Kennedy, John F. "Inaugural Address." Washington, D.C., January 20, 1961. Presidential Address.

Which of the choices below is an example of President Kennedy's use of historical background in his speech?
A begin anew the quest for peace
B we offer not a pledge but a request
C dark powers of destruction unleashed by science
D nations who would make themselves our adversary