C. The poet describes how the narrator is slowing down to focus on details.
In the third stanza of the poem, the poet describes how the narrator "lazily" lounges through "labyrinthine corridors," and how the narrator's eyes are "suddenly altered" as he peers into an office he does not know. These details suggest that the narrator is slowing down and becoming more attentive to his surroundings, perhaps as a result of the "immense will" he felt in the previous stanza. This slowing down allows him to focus on details that he might not have noticed before, and to wonder at the "startled face" he sees in the office. Therefore, option C accurately reflects how the poet develops the narrator's point of view in the third stanza.
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