I would say probably B) The image of wild and lone.
Buuttt.. It could possibly be something different.. (Maybe C?)
C Subordinate is not a type of verbal phrase
I believe the correct answer is to help the reader visualize a view where water and sky are difficult to tell apart.
The author is trying to portray an image where the water and the sky are somehow blending into each other - you can't tell where one ends and the other one begins, because both items are colored similarly - various shades of blue.
Tennessee's partner chronicles and inexplicable bond between two men, Tennessee and partner, both crude, unfettered mining camp l men. the basis for their bond is never explained, but it's durable strength is revealed in the fact that their friend while survives a breach of its faith: after Tennessee runs off with his partner's wife, he returnes to Sandy bar and is welcomed back by his friend with out rancor or resentment. theirs is a friendship that transcends marriage tirs- at least for the protagonist, Tennessee's Partner.