The correct answer is C) they stopped the movement of the poem.
The significance of the exclamations "Halt!” and "Fire!” is t"hey stopped the movement of the poem."
We are referring to an excerpt of the poem "Barbara Frietchie," written by John Greenleaf Whittier.
The excerpt is this: "Under his slouched hat left and right. He glanced: the old flag met his sight. Halt!-the dust-brown ranks stood fast. Fire!-out blazed the rifle blast."
The other options of the question are A) they foreshadow what will happen next. B) they move the action forward with dialogue. D) they describe the sound of Jackson's voice.