At once a voice arose among
The bleak twigs overhead
<span>In a full-hearted evensong
</span>Had chosen thus to fling his soul
<span>Upon the growing gloom.</span>
Since the 'inciting incident' is the one which starts all the problems in a literary work, the answer is B, 'establishment of the central conflict followed by the conflict increasing and a climax'.
Complex and compound sentences.
A - incorrect as it does have a hero.
B - correct. The fact that it tells a long narrative story, among other things (like that it tells the story of the hero) makes it an epic poem.
C - incorrect as it is one long story
D - incorrect, using words in a poetic manner is not enough to consider writing an epic poem.