Now the trumpet summons us again—not as a call to bear arms, though arms we need; not as a call to battle, though embattled we are—but a call to bear the burden of a long twilight struggle, year in and year out, "rejoicing in hope, patient in tribulation"—a struggle against the common enemies of man: tyranny, poverty, disease, and war itself. can we forge against these enemies a grand and global alliance, north and south, east and west, that can assure a more fruitful life for all mankind? will you join in that historic effort? . . which is president kennedy’s intent when using questions in the last paragraph of this excerpt? a)he is attempting to directly involve listeners and motivate them in his causes. b)he is setting up what topics he will cover in the remainder of his speech. c)he is striving to keep listeners interested in his speech with stylistic variety.