Which line in this excerpt from Walt Whitman's "O Captain! My Captain!" reflects the theme of patriotism that dominates the poem?
 A. O Captain! my Captain! rise up and hear the bells;
 B.Rise up—for you the flag is flung—for you the bugle trills,
 C.For you they call, the swaying mass, their eager faces turning;
 D.It is some dream that on the deck,