The answer is C: personification.
Personification is a figure of speech in which a non-human thing or event is represented as if possessing human characteristics, traits or behaviors.
In the passage above, the night, as it leaves behind the day and becomes more fully realized is being compared to a person that would behave in such a way that he or she would force his or her thick, warm, and somber corporality upon something or someone, in this case, a yacht.
