The response that best addresses how the structure of the poem affects its meaning is:
The use of three quatrains gives a consistent, ordered quality to the speaker’s whimsical descriptions of the dream.
This response highlights how the formal structure of three quatrains contributes to the overall dreamlike and whimsical atmosphere of the poem, enhancing the reader's experience of the speaker's journey to the Land of Night. The consistent structure allows for a flowing narrative that mirrors the fluidity of dreams.