How does this from "The Walrus and the Carpenter" contribute to the meaning of the poem?

'The sun was shining on the sea, Shining with all its might; he did his very best to make the billows smooth and bright - And this was very odd, because it was the middle of the night.

A. It describes two of the main characters in the poem
B. It expresses the deeper theme of the poem
C. it introduces the nonsense tone of the poem