In "Dover Beach," the "distant northern sea" is contrasted to: -Ionian -Sea of Faith -girdle -tremulous cadence

It is always important with these multiple choice
questions to read the quote in context of the lines around it and then to use a process
of elimination to go through the various options one by one, deleting those that you
know it definitely isn't before finally selecting the right one. Reading this poem
carefully, you can see that the sound of the waves of this "distant northern sea" then
prompts the speaker to compare this sea to the metaphorical "Sea of Faith." This
metaphor stands for the beliefs that the speaker fears are disappearing from the world.
Just as the tide of the sea withdraws, so the speaker fears that the tide of the Sea of
Faith is withdrawing, indicating that something protective and powerful is leaving the
world, exposing it to danger:

readability="14">

The Sea of
Faith

Was once, too, at the full, and round earth's
shore

Lay like the folds of a bright girdle
furled.

But now I only
hear

Its melnacholy, long, withdrawing
roar...

So the correct answer
is that the "sea" is compared to the "Sea of Faith," the poignant metaphor that Arnold
uses to discuss the decline of faith in his context.