Which of these excerpts is most clearly an example of narrative poetry?

a. "and all that's best as dark and bright/meet in her aspect and her "
b. "and on her dulcimer she played,/singing of mount abora."
c. "one shade the more, one ray the less/had half impaired the nameless "
d. "of that colossal wreck, boundless and bare/the stretch far away."

I think the one that is clearly an example of a narrative poetry would be: B. "And on her dulcimer, she played,/Singing of Mount Abora."

Narrative poetry mostly tells a fiction in the form of Poetry. We could distinguish it by spotting a name of a character or unique setting. In this case, she played,/Singing of Mount Abora  is pretty much the phrases that gave it away.