How does the structure of this verse influence the poem?

out of an unseen quarry evermore
furnished with tile, the fierce artificer
curves his white bastions with projected roof
round every windward stake, or tree, or door.
a. the increasing line lengths enhance the mood of the verse.
b. the increasing line lengths to build up the emotion expressed in the verse.
c. the increasing line lengths enhance the vividness of the imagery in the verse.
d. the increasing line lengths enhance the sound of the verse.