I would say that the answer is 'the poet uses dashes to slow readers down as they read through the poem', but that's kind of debatable. It doesn't fit any of the other answers, though.
I believe the answer is D
The banks <u>don't</u><u> </u><u>open</u><u> </u> on Sundays.....
What time <u>does</u><u> </u><u>the</u><u> </u><u>train</u><u> </u><u>leave</u><u> </u>.......