In this excerpt from "Song of Myself", the literary device that Whitman uses to address the sea is (C.) apostrophe.
Apostrophe is a literary device that consists in speaking directly to an inanimate object or to someone that cannot answer.<u> In this excerpt from Whitman's poem, the speaker is talking to the sea as if it was real human being capable of understanding the way he feels</u> ("Cushion me soft, rock me in billowy drowse, Dash me with amorous wet, I can repay you"). The use of apostrophe allows the poet to produce a more creative perspective and to develop a dramatic effect.